Database Queries (mysql)

Lab Manual (Database Systems) Dr. Osman Khalid COMATS Institute of Information Technology, Abbottabad, Pakistan http://osman.pakproject.com

Contents LAB 01—Creating Configuring the database................................................................................................. 5 Command to see the existing databases in MySql Server ........................................................................ 6 Create a database and Populate values .................................................................................................... 6 LAB 02—update database structure ........................................................................................................... 25 Command to show the tables in a database .......................................................................................... 26 Retrieve System Time: ............................................................................................................................ 26 Add Two Number: ................................................................................................................................... 26 CREATE NEW TABLE: ............................................................................................................................... 26 Adding/Dropping Primary Key: ............................................................................................................... 26 Adding Column and Drop Column from Table ........................................................................................ 26 LAB 03—Change table structure/data ........................................................................................................ 28 Renaming Column in Table ..................................................................................................................... 29 Setting Default Value for a Column: ....................................................................................................... 29 Drop Table............................................................................................................................................... 29 Empty Table: ........................................................................................................................................... 29 Delete a single row from table................................................................................................................ 29 Delete all rows from table: ..................................................................................................................... 29 LAB 04—data copying/deletion .................................................................................................................. 30 Transfer/Copy Data from table1 to table2 with same table structure ................................................... 31 1

Delete a single row from table:............................................................................................................... 31 UPDATE a row in table: ........................................................................................................................... 31 LAB 05—Auto-increment primary key ........................................................................................................ 32 Creating an AUTO INCREMENT PRIMARY KEY: ....................................................................................... 33 Start Auto Increment with user specified value : ................................................................................... 33 LAB 06—database indexes .......................................................................................................................... 35 Creating Indexes : ................................................................................................................................... 36 Drop Indexes : ......................................................................................................................................... 37 LAB 07—create index on foreign keys ........................................................................................................ 38 Creating index on foreign key : ............................................................................................................... 39 LAB 08—select clause in detail ................................................................................................................... 40 Clauses of the SELECT Statement: .......................................................................................................... 41 Two Special Keywords used in SELECT:................................................................................................... 41 LAB 09—Creating Alias in database ............................................................................................................ 43 Using Alias in SELECT Statement: ............................................................................................................ 44 LAB 10—sorting the data ............................................................................................................................ 45 Rearranging column Order in SELECT Query: ......................................................................................... 46 LAB 11—using expressions and functions .................................................................................................. 47 Using Expressions:................................................................................................................................... 48 Using Functions: ...................................................................................................................................... 48 LAB 12—built-in functions .......................................................................................................................... 50 COUNT : Returns single row.................................................................................................................... 51 Difference between COUNT(*) and COUNT(ColumnName) ................................................................... 51 LAB 13—NULL values .................................................................................................................................. 53 Using Comparison Operators .................................................................................................................. 54 Using NULL Values .................................................................................................................................. 54 LAB 14—logical operators........................................................................................................................... 55 Using Boolean Operators (Logical Operators): ....................................................................................... 56 Using Ranges for Qualification: ............................................................................................................... 56 Using DISTINCT values: ........................................................................................................................... 57 LAB 15—understanding in and not in ......................................................................................................... 58 Using IN and NOT IN Lists: ...................................................................................................................... 59 2

Sorting Results: The ORDER BY Clause ................................................................................................... 59 LAB 16—the use of “limit” operator ........................................................................................................... 60 Using LIMIT :............................................................................................................................................ 61 LAB 17—Group by and having clause ......................................................................................................... 62 Categorizing Results: The GROUP BY Clause: ......................................................................................... 63 Qualify Results by Categories: ................................................................................................................ 63 LAB 18—defining views............................................................................................................................... 65 Using and Defining Views: ...................................................................................................................... 66 LAB 19—queries involving multiple tables ................................................................................................. 67 Processing Multiple Tables: .................................................................................................................... 68 LAB 20—different types of joins ................................................................................................................. 69 Outer Join:............................................................................................................................................... 70 Left OUTER Join ....................................................................................................................................... 70 LAB 21—Self join ......................................................................................................................................... 72 Sample join Involving four tables:........................................................................................................... 73 Self Join: .................................................................................................................................................. 73 LAB 22—Subqueries .................................................................................................................................... 75 Subqueries .............................................................................................................................................. 76 LAB 23—in, not in, exists, not exists ........................................................................................................... 78 Using the NOT IN qualifier: ..................................................................................................................... 79 Using EXISTS and NOT EXISTS: ................................................................................................................ 79 EXISTS versus IN and NOT EXISTS versus NOT IN.................................................................................... 79 LAB 24—derived tables and sub-queries .................................................................................................... 81 Correlated Subqueries: ........................................................................................................................... 82 Using Derived Tables:.............................................................................................................................. 82 LAB 25—union operator & type conversion ............................................................................................... 83 Union Operator: ...................................................................................................................................... 84 Data Type Conversion: ............................................................................................................................ 84 LAB 26—conditional expression and trigger............................................................................................... 85 Conditional Expressions: ......................................................................................................................... 86 Triggers.................................................................................................................................................... 86 LAB 27—introduction to stored procedures............................................................................................... 89 3

Stored Procedures: ................................................................................................................................. 90 LAB 28—stored procedure – single input ................................................................................................... 91 STORED PROCEDURE WITH A SINGLE INPUT PARAMETER ..................................................................... 92 LAB 29—stored procedures – input/output ............................................................................................... 93 STORED PROCEDURE WITH A SINGLE INPUT and A SINGLE OUTPUT PARAMETER................................ 94 LAB 30—stored procedure returning values .............................................................................................. 95 STORED PROCEDURE WITH A SINGLE INPUT PARAMETER and TWO OUTPUT PARAMETERS ............... 96 LAB 31—using mysql functions ................................................................................................................... 97 MySQL FUNCTIONS ................................................................................................................................. 98 LAB 32—Connecting mysql with php .......................................................................................................... 99 CONNECTING PHP with MySQL............................................................................................................. 100

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LAB 01—CREATING CONFIGURING THE DATABASE Objectives: The objective of this lab is to make students learn how to show existing databases, how to create a new database and populate the database with data, and run simple select queries.

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Command to see the existing databases in MySql Server SHOW DATABASES;

Create a database and Populate values In this lab we will learn the following: Creation of database Pineview Creation of tables Setting up of constraints Inserting values in tables.

STEP-1 COPY - PASTE THE BELOW COMMANDS IN QUERY EDITOR CREATE SCHEMA PINEVIEW;

STEP-2 COPY - PASTE THE BELOW COMMANDS IN QUERY EDITOR use pineview;

CREATE TABLE Customer_T (CustomerID

int

NOT NULL,

CustomerName

VARCHAR(25)

CustomerAddress

VARCHAR(30) ,

CustomerCity CustomerState

NOT NULL,

VARCHAR(20) , CHAR(2)

,

CustomerPostalCode VARCHAR(10) ,

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CONSTRAINT Customer_PK PRIMARY KEY (CustomerID)); CREATE TABLE Territory_T (TerritoryID

int

TerritoryName

NOT NULL, VARCHAR(50) ,

CONSTRAINT Territory_PK PRIMARY KEY (TerritoryID));

CREATE TABLE DoesBusinessIn_T (CustomerID

int

TerritoryID

int

NOT NULL, NOT NULL,

CONSTRAINT DoesBusinessIn_PK PRIMARY KEY (CustomerID, TerritoryID), CONSTRAINT DoesBusinessIn_FK1 FOREIGN KEY (CustomerID) REFERENCES Customer_T(CustomerID), CONSTRAINT DoesBusinessIn_FK2 FOREIGN KEY (TerritoryID) REFERENCES Territory_T(TerritoryID)); CREATE TABLE Employee_T (EmployeeID

VARCHAR(10) NOT NULL,

EmployeeName

VARCHAR(25) ,

EmployeeAddress

VARCHAR(30) ,

EmployeeBirthDate DATE EmployeeCity EmployeeState EmployeeZip

,

VARCHAR(20) , CHAR(2)

,

VARCHAR(10) ,

EmployeeDateHired DATE

,

EmployeeSupervisor VARCHAR(10) , CONSTRAINT Employee_PK PRIMARY KEY (EmployeeID));

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CREATE TABLE Skill_T (SkillID

VARCHAR(12) NOT NULL,

SkillDescription VARCHAR(30) , CONSTRAINT Skill_PK PRIMARY KEY (SkillID));

CREATE TABLE EmployeeSkills_T (EmployeeID SkillID

VARCHAR(10) NOT NULL, VARCHAR(12) NOT NULL,

CONSTRAINT EmployeeSkills_PK PRIMARY KEY (EmployeeID, SkillID), CONSTRAINT EmployeeSkills_FK1 FOREIGN KEY (EmployeeID) REFERENCES Employee_T(EmployeeID), CONSTRAINT EmployeeSkills_FK2 FOREIGN KEY (SkillID) REFERENCES Skill_T(SkillID));

CREATE TABLE Order_T (OrderID

int NOT NULL,

CustomerID OrderDate

int ,

TIMESTAMP DEFAULT CURRENT_TIMESTAMP

,

CONSTRAINT Order_PK PRIMARY KEY (OrderID), CONSTRAINT Order_FK1 FOREIGN KEY (CustomerID) REFERENCES Customer_T(CustomerID));

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CREATE TABLE WorkCenter_T (WorkCenterID

VARCHAR(12) NOT NULL,

WorkCenterLocation VARCHAR(30) , CONSTRAINT WorkCenter_PK PRIMARY KEY (WorkCenterID));

CREATE TABLE ProductLine_T (ProductLineID

int NOT NULL,

ProductLineName

VARCHAR(50) ,

CONSTRAINT ProductLine_PK PRIMARY KEY (ProductLineID));

CREATE TABLE Product_T (ProductID ProductLineID

int NOT NULL, int ,

ProductDescription VARCHAR(50) , ProductFinish

VARCHAR(20) ,

ProductStandardPrice DECIMAL(6,2) , CONSTRAINT Product_PK PRIMARY KEY (ProductID), CONSTRAINT Product_FK1 FOREIGN KEY (ProductLineID) REFERENCES ProductLine_T(ProductLineID));

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CREATE TABLE ProducedIn_T (ProductID

int

WorkCenterID

NOT NULL,

VARCHAR(12) NOT NULL,

CONSTRAINT ProducedIn_PK PRIMARY KEY (ProductID, WorkCenterID), CONSTRAINT ProducedIn_FK1 FOREIGN KEY (ProductID) REFERENCES Product_T(ProductID), CONSTRAINT ProducedIn_FK2 FOREIGN KEY (WorkCenterID) REFERENCES WorkCenter_T(WorkCenterID));

CREATE TABLE OrderLine_T (OrderID ProductID

int NOT NULL, int NOT NULL,

OrderedQuantity

int ,

CONSTRAINT OrderLine_PK PRIMARY KEY (OrderID, ProductID), CONSTRAINT OrderLine_FK1 FOREIGN KEY (OrderID) REFERENCES Order_T(OrderID), CONSTRAINT OrderLine_FK2 FOREIGN KEY (ProductID) REFERENCES Product_T(ProductID));

CREATE TABLE RawMaterial_T (MaterialID MaterialName

VARCHAR(12) NOT NULL, VARCHAR(30) ,

MaterialStandardCost DECIMAL(6,2) , UnitOfMeasure

VARCHAR(10) ,

CONSTRAINT RawMaterial_PK PRIMARY KEY (MaterialID));

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CREATE TABLE Salesperson_T (SalespersonID

int NOT NULL,

SalespersonName

VARCHAR(25) ,

SalespersonPhone VARCHAR(50) , SalespersonFax TerritoryID

VARCHAR(50) , int ,

CONSTRAINT Salesperson_PK PRIMARY KEY (SalesPersonID), CONSTRAINT Salesperson_FK1 FOREIGN KEY (TerritoryID) REFERENCES Territory_T(TerritoryID));

CREATE TABLE Vendor_T (VendorID

int NOT NULL,

VendorName

VARCHAR(25) ,

VendorAddress

VARCHAR(30) ,

VendorCity VendorState VendorZipcode VendorFax

VARCHAR(20) , CHAR(2)

,

VARCHAR(50) , VARCHAR(10) ,

VendorPhone

VARCHAR(10) ,

VendorContact

VARCHAR(50) ,

VendorTaxID

VARCHAR(50) ,

CONSTRAINT Vendor_PK PRIMARY KEY (VendorID));

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CREATE TABLE Supplies_T (VendorID

int NOT NULL,

MaterialID

VARCHAR(12) NOT NULL,

SuppliesUnitPrice DECIMAL(6,2) , CONSTRAINT Supplies_PK PRIMARY KEY (VendorID, MaterialID), CONSTRAINT Supplies_FK1 FOREIGN KEY (MaterialId) REFERENCES RawMaterial_T(MaterialID), CONSTRAINT Supplies_FK2 FOREIGN KEY (VendorID) REFERENCES Vendor_T(VendorID));

CREATE TABLE Uses_T (ProductID

int NOT NULL,

MaterialID

VARCHAR(12) NOT NULL,

GoesIntoQuantity INTEGER

,

CONSTRAINT Uses_PK PRIMARY KEY (ProductID, MaterialID), CONSTRAINT Uses_FK1 FOREIGN KEY (ProductID) REFERENCES Product_T(ProductID), CONSTRAINT Uses_FK2 FOREIGN KEY (MaterialID) REFERENCES RawMaterial_T(MaterialID));

CREATE TABLE WorksIn_T (EmployeeID WorkCenterID

VARCHAR(10) NOT NULL, VARCHAR(12) NOT NULL,

CONSTRAINT WorksIn_PK PRIMARY KEY (EmployeeID, WorkCenterID), CONSTRAINT WorksIn_FK1 FOREIGN KEY (EmployeeID) REFERENCES Employee_T(EmployeeID), CONSTRAINT WorksIn_FK2 FOREIGN KEY (WorkCenterID) REFERENCES WorkCenter_T(WorkCenterID));

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delete from Uses_T; delete from WorksIn_T; delete from WorkCenter_T; delete from DoesBusinessIn_T; delete from EmployeeSkills_T; delete from Supplies_T; delete from ProducedIn_T; delete from OrderLine_T; delete from Product_T; delete from ProductLine_T; delete from Order_T; delete from Salesperson_T; delete from Vendor_T; delete from Skill_T; delete from RawMaterial_T; delete from Territory_T; delete from Employee_T; delete from Customer_T;

INSERT INTO Customer_T (CustomerID, CustomerName, CustomerAddress, CustomerCity, CustomerState, CustomerPostalCode) VALUES (1, 'Contemporary Casuals', '1355 S Hines Blvd', 'Gainesville', 'FL', '32601-2871'); INSERT INTO Customer_T (CustomerID, CustomerName, CustomerAddress, CustomerCity, CustomerState, CustomerPostalCode) VALUES (2, 'Value Furniture', '15145 S.W. 17th St.', 'Plano', 'TX', '75094-7743');

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INSERT INTO Customer_T (CustomerID, CustomerName, CustomerAddress, CustomerCity, CustomerState, CustomerPostalCode) VALUES (3, 'Home Furnishings', '1900 Allard Ave.', 'Albany', 'NY', '12209-1125'); INSERT INTO Customer_T (CustomerID, CustomerName, CustomerAddress, CustomerCity, CustomerState, CustomerPostalCode) VALUES (4, 'Eastern Furniture', '1925 Beltline Rd.', 'Carteret', 'NJ', '07008-3188'); INSERT INTO Customer_T (CustomerID, CustomerName, CustomerAddress, CustomerCity, CustomerState, CustomerPostalCode) VALUES (5, 'Impressions', '5585 Westcott Ct.', 'Sacramento', 'CA', '94206-4056'); INSERT INTO Customer_T (CustomerID, CustomerName, CustomerAddress, CustomerCity, CustomerState, CustomerPostalCode) VALUES (6, 'Furniture Gallery', '325 Flatiron Dr.', 'Boulder', 'CO', '80514-4432'); INSERT INTO Customer_T (CustomerID, CustomerName, CustomerAddress, CustomerCity, CustomerState, CustomerPostalCode) VALUES (7, 'Period Furniture', '394 Rainbow Dr.', 'Seattle', 'WA', '97954-5589'); INSERT INTO Customer_T (CustomerID, CustomerName, CustomerAddress, CustomerCity, CustomerState, CustomerPostalCode) VALUES (8, 'California Classics', '816 Peach Rd.', 'Santa Clara', 'CA', '96915-7754'); INSERT INTO Customer_T (CustomerID, CustomerName, CustomerAddress, CustomerCity, CustomerState, CustomerPostalCode) VALUES (9, 'M and H Casual Furniture', '3709 First Street', 'Clearwater', 'FL', '34620-2314'); INSERT INTO Customer_T (CustomerID, CustomerName, CustomerAddress, CustomerCity, CustomerState, CustomerPostalCode) VALUES (10, 'Seminole Interiors', '2400 Rocky Point Dr.', 'Seminole', 'FL', '34646-4423'); INSERT INTO Customer_T (CustomerID, CustomerName, CustomerAddress, CustomerCity, CustomerState, CustomerPostalCode) VALUES (11, 'American Euro Lifestyles', '2424 Missouri Ave N.', 'Prospect Park', 'NJ', '07508-5621'); INSERT INTO Customer_T (CustomerID, CustomerName, CustomerAddress, CustomerCity, CustomerState, CustomerPostalCode) VALUES (12, 'Battle Creek Furniture', '345 Capitol Ave. SW', 'Battle Creek', 'MI', '49015-3401');

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INSERT INTO Customer_T (CustomerID, CustomerName, CustomerAddress, CustomerCity, CustomerState, CustomerPostalCode) VALUES (13, 'Heritage Furnishings', '66789 College Ave.', 'Carlisle', 'PA', '17013-8834'); INSERT INTO Customer_T (CustomerID, CustomerName, CustomerAddress, CustomerCity, CustomerState, CustomerPostalCode) VALUES (14, 'Kaneohe Homes', '112 Kiowai St.', 'Kaneohe', 'HI', '96744-2537'); INSERT INTO Customer_T (CustomerID, CustomerName, CustomerAddress, CustomerCity, CustomerState, CustomerPostalCode) VALUES (15, 'Mountain Scenes', '4132 Main Street', 'Ogden', 'UT', '84403-4432');

INSERT INTO Territory_T (TerritoryID, TerritoryName) VALUES (1, 'SouthEast'); INSERT INTO Territory_T (TerritoryID, TerritoryName) VALUES (2, 'SouthWest'); INSERT INTO Territory_T (TerritoryID, TerritoryName) VALUES (3, 'NorthEast'); INSERT INTO Territory_T (TerritoryID, TerritoryName) VALUES (4, 'NorthWest'); INSERT INTO Territory_T (TerritoryID, TerritoryName) VALUES (5, 'Central');

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INSERT INTO DoesBusinessIn_T (CustomerID, TerritoryID) VALUES (1, 1); INSERT INTO DoesBusinessIn_T (CustomerID, TerritoryID) VALUES (1, 2); INSERT INTO DoesBusinessIn_T (CustomerID, TerritoryID) VALUES (2, 2); INSERT INTO DoesBusinessIn_T (CustomerID, TerritoryID) VALUES (3, 3); INSERT INTO DoesBusinessIn_T (CustomerID, TerritoryID) VALUES (4, 3); INSERT INTO DoesBusinessIn_T (CustomerID, TerritoryID) VALUES (5, 2); INSERT INTO DoesBusinessIn_T (CustomerID, TerritoryID) VALUES (6, 5);

INSERT INTO Employee_T (EmployeeID, EmployeeName, EmployeeAddress, EmployeeCity, EmployeeState, EmployeeZip, EmployeeDateHired, EmployeeBirthDate, EmployeeSupervisor) VALUES ('123-44-345', 'Jim Jason', '2134 Hilltop Rd', '', 'TN', '', '12/Jun/99', '', '454-56-768');

INSERT INTO Employee_T (EmployeeID, EmployeeName, EmployeeAddress, EmployeeCity, EmployeeState, EmployeeZip, EmployeeDateHired, EmployeeBirthDate, EmployeeSupervisor) VALUES ('454-56-768', 'Robert Lewis', '17834 Deerfield Ln', 'Nashville', 'TN', '', '01/Jan/99', '', '');

Insert into Employee_T (EmployeeID,EmployeeName,EmployeeAddress,EmployeeCity,EmployeeState,EmployeeZip,EmployeeDateHired,E mployeeBirthDate,EmployeeSupervisor) values ('123-44-346','Phil Morris','2134 Hilltop Rd','Knoxville','TN',null,'12-JUN-99' ,'12-JUN-99','454-56-768');

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Insert into Employee_T (EmployeeID,EmployeeName,EmployeeAddress,EmployeeCity,EmployeeState,EmployeeZip,EmployeeDateHired,E mployeeBirthDate,EmployeeSupervisor) values ('332445667','Lawrence Haley','5970 Spring Crest Rd','Nashville','TN','54545','2008-7-04','2008-7-04','45456-768');

Insert into Employee_T (EmployeeID,EmployeeName,EmployeeAddress,EmployeeCity,EmployeeState,EmployeeZip,EmployeeDateHired,E mployeeBirthDate,EmployeeSupervisor) values ('454-56-769','Robert Lewis','17834 Deerfield Ln','Knoxville','TN','55555','2008-7-04','2008-7-04','123-44345');

Insert into Employee_T (EmployeeID,EmployeeName,EmployeeAddress,EmployeeCity,EmployeeState,EmployeeZip,EmployeeDateHired,E mployeeBirthDate,EmployeeSupervisor) values ('555955585','Mary Smith','75 Jane Lane','Clearwater','FL','33879','2008-7-04','2008-7-04','332445667');

Insert into Employee_T (EmployeeID,EmployeeName,EmployeeAddress,EmployeeCity,EmployeeState,EmployeeZip,EmployeeDateHired,E mployeeBirthDate,EmployeeSupervisor) values ('Laura','Laura Ellenburg','5342 Picklied Trout Lane','Nashville','TN','38010','2008-7-04',null,'454-56-768');

INSERT INTO Skill_T (SkillID, SkillDescription) VALUES ('BS12', '12in Band Saw'); INSERT INTO Skill_T (SkillID, SkillDescription) VALUES ('QC1', 'Quality Control'); INSERT INTO Skill_T (SkillID, SkillDescription) VALUES ('RT1', 'Router'); INSERT INTO Skill_T (SkillID, SkillDescription) VALUES ('SO1', 'Sander-Orbital');

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INSERT INTO Skill_T (SkillID, SkillDescription) VALUES ('SB1', 'Sander-Belt'); INSERT INTO Skill_T (SkillID, SkillDescription) VALUES ('TS10', '10in Table Saw'); INSERT INTO Skill_T (SkillID, SkillDescription) VALUES ('TS12', '12in Table Saw'); INSERT INTO Skill_T (SkillID, SkillDescription) VALUES ('UC1', 'Upholstery Cutter'); INSERT INTO Skill_T (SkillID, SkillDescription) VALUES ('US1', 'Upholstery Sewer'); INSERT INTO Skill_T (SkillID, SkillDescription) VALUES ('UT1', 'Upholstery Tacker');

INSERT INTO EmployeeSkills_T (EmployeeID, SkillID) VALUES ('123-44-345', 'BS12'); INSERT INTO EmployeeSkills_T (EmployeeID, SkillID) VALUES ('123-44-345', 'RT1'); INSERT INTO EmployeeSkills_T (EmployeeID, SkillID) VALUES ('454-56-768', 'BS12');

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INSERT INTO Order_T (OrderID, OrderDate, CustomerID) VALUES (1001, '21/Oct/10', 1); INSERT INTO Order_T (OrderID, OrderDate, CustomerID) VALUES (1002, '21/Oct/10', 8); INSERT INTO Order_T (OrderID, OrderDate, CustomerID) VALUES (1003, '22/Oct/10', 15); INSERT INTO Order_T (OrderID, OrderDate, CustomerID) VALUES (1004, '22/Oct/10', 5); INSERT INTO Order_T (OrderID, OrderDate, CustomerID) VALUES (1005, '24/Oct/10', 3); INSERT INTO Order_T (OrderID, OrderDate, CustomerID) VALUES (1006, '24/Oct/10', 2); INSERT INTO Order_T (OrderID, OrderDate, CustomerID) VALUES (1007, '27/Oct/10', 11); INSERT INTO Order_T (OrderID, OrderDate, CustomerID) VALUES (1008, '30/Oct/10', 12); INSERT INTO Order_T (OrderID, OrderDate, CustomerID) VALUES (1009, '05/Nov/10', 4); INSERT INTO Order_T (OrderID, OrderDate, CustomerID) VALUES (1010, '05/Nov/10', 1);

INSERT INTO ProductLine_T (ProductLineID, ProductLineName) VALUES (1, 'Cherry Tree');

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INSERT INTO ProductLine_T (ProductLineID, ProductLineName) VALUES (2, 'Scandinavia'); INSERT INTO ProductLine_T (ProductLineID, ProductLineName) VALUES (3, 'Country Look');

INSERT INTO Product_T (ProductID, ProductDescription, ProductFinish, ProductStandardPrice, ProductLineID) VALUES (1, 'End Table', 'Cherry', 175, 1); INSERT INTO Product_T (ProductID, ProductDescription, ProductFinish, ProductStandardPrice, ProductLineID) VALUES (2, 'Coffee Table', 'Natural Ash', 200, 2); INSERT INTO Product_T (ProductID, ProductDescription, ProductFinish, ProductStandardPrice, ProductLineID) VALUES (3, 'Computer Desk', 'Natural Ash', 375, 2); INSERT INTO Product_T (ProductID, ProductDescription, ProductFinish, ProductStandardPrice, ProductLineID) VALUES (4, 'Entertainment Center', 'Natural Maple', 650, 3); INSERT INTO Product_T (ProductID, ProductDescription, ProductFinish, ProductStandardPrice, ProductLineID) VALUES (5, 'Writers Desk', 'Cherry', 325, 1); INSERT INTO Product_T (ProductID, ProductDescription, ProductFinish, ProductStandardPrice, ProductLineID) VALUES (6, '8-Drawer Desk', 'White Ash', 750, 2); INSERT INTO Product_T (ProductID, ProductDescription, ProductFinish, ProductStandardPrice, ProductLineID) VALUES (7, 'Dining Table', 'Natural Ash', 800, 2); INSERT INTO Product_T (ProductID, ProductDescription, ProductFinish, ProductStandardPrice, ProductLineID) VALUES (8, 'Computer Desk', 'Walnut', 250, 3);

INSERT INTO OrderLine_T (OrderID, ProductID, OrderedQuantity) VALUES (1001, 1, 2);

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INSERT INTO OrderLine_T (OrderID, ProductID, OrderedQuantity) VALUES (1001, 2, 2); INSERT INTO OrderLine_T (OrderID, ProductID, OrderedQuantity) VALUES (1001, 4, 1); INSERT INTO OrderLine_T (OrderID, ProductID, OrderedQuantity) VALUES (1002, 3, 5); INSERT INTO OrderLine_T (OrderID, ProductID, OrderedQuantity) VALUES (1003, 3, 3); INSERT INTO OrderLine_T (OrderID, ProductID, OrderedQuantity) VALUES (1004, 6, 2); INSERT INTO OrderLine_T (OrderID, ProductID, OrderedQuantity) VALUES (1004, 8, 2); INSERT INTO OrderLine_T (OrderID, ProductID, OrderedQuantity) VALUES (1005, 4, 3); INSERT INTO OrderLine_T (OrderID, ProductID, OrderedQuantity) VALUES (1006, 4, 1); INSERT INTO OrderLine_T (OrderID, ProductID, OrderedQuantity) VALUES (1006, 5, 2); INSERT INTO OrderLine_T (OrderID, ProductID, OrderedQuantity) VALUES (1006, 7, 2); INSERT INTO OrderLine_T (OrderID, ProductID, OrderedQuantity) VALUES (1007, 1, 3); INSERT INTO OrderLine_T (OrderID, ProductID, OrderedQuantity) VALUES (1007, 2, 2); INSERT INTO OrderLine_T (OrderID, ProductID, OrderedQuantity) VALUES (1008, 3, 3);

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INSERT INTO OrderLine_T (OrderID, ProductID, OrderedQuantity) VALUES (1008, 8, 3); INSERT INTO OrderLine_T (OrderID, ProductID, OrderedQuantity) VALUES (1009, 4, 2); INSERT INTO OrderLine_T (OrderID, ProductID, OrderedQuantity) VALUES (1009, 7, 3); INSERT INTO OrderLine_T (OrderID, ProductID, OrderedQuantity) VALUES (1010, 8, 10);

INSERT INTO Salesperson_T (SalesPersonID, SalesPersonName, SalesPersonPhone, SalesPersonFax, TerritoryID) VALUES (1, 'Doug Henny', '8134445555', '', 1); INSERT INTO Salesperson_T (SalesPersonID, SalesPersonName, SalesPersonPhone, SalesPersonFax, TerritoryID) VALUES (2, 'Robert Lewis', '8139264006', '', 2); INSERT INTO Salesperson_T (SalesPersonID, SalesPersonName, SalesPersonPhone, SalesPersonFax, TerritoryID) VALUES (3, 'William Strong', '5053821212', '', 3); INSERT INTO Salesperson_T (SalesPersonID, SalesPersonName, SalesPersonPhone, SalesPersonFax, TerritoryID) VALUES (4, 'Julie Dawson', '4355346677', '', 4); INSERT INTO Salesperson_T (SalesPersonID, SalesPersonName, SalesPersonPhone, SalesPersonFax, TerritoryID) VALUES (5, 'Jacob Winslow', '2238973498', '', 5);

INSERT INTO WorkCenter_T (WorkCenterID, WorkCenterLocation) VALUES ('SM1', 'Main Saw Mill'); INSERT INTO WorkCenter_T (WorkCenterID, WorkCenterLocation)

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VALUES ('WR1', 'Warehouse and Receiving');

/* INSERT INTO WorksIn_T (EmployeeID, WorkCenterID) VALUES ('123-44-345', 'SM1'); INSERT INTO WorksIn_T (EmployeeID, WorkCenterID) VALUES ('454-56-768', 'Tampa1'); */

describe Uses_T; describe WorksIn_T; describe WorkCenter_T; describe DoesBusinessIn_T; describe EmployeeSkills_T; describe Supplies_T; describe ProducedIn_T; describe OrderLine_T; describe Product_T; describe ProductLine_T; describe Order_T; describe Salesperson_T; describe Vendor_T; describe Skill_T; describe RawMaterial_T; describe Territory_T;

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describe Employee_T; describe Customer_T;

select * from Uses_T; select * from WorksIn_T; select * from WorkCenter_T; select * from DoesBusinessIn_T; select * from EmployeeSkills_T; select * from Supplies_T; select * from ProducedIn_T; select * from OrderLine_T; select * from Product_T; select * from ProductLine_T; select * from Order_T; select * from Salesperson_T; select * from Vendor_T; select * from Skill_T; select * from RawMaterial_T; select * from Territory_T; select * from Employee_T; select * from Customer_T;

COMMIT;

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LAB 02—UPDATE DATABASE STRUCTURE Objectives: The objective of this lab is to familiarize students with basic select statement, how to add/drop a primary key, and how to add/drop a column from table.

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Command to show the tables in a database Use PineView; SHOW TABLES;

Retrieve System Time: SELECT CURTIME();

Add Two Number: SELECT 8+4;

CREATE NEW TABLE: CREATE TABLE temp( ID INT, Name VARCHAR(10) ); DESCRIBE temp;

Adding/Dropping Primary Key: ALTER TABLE temp ADD CONSTRAINT pk_ID PRIMARY KEY (id); ALTER TABLE temp DROP PRIMARY KEY;

Adding Column and Drop Column from Table ALTER TABLE temp ADD COLUMN address VARCHAR(100); ALTER TABLE temp 26

DROP COLUMN address;

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LAB 03—CHANGE TABLE STRUCTURE/DATA Objectives: The students will learn how to rename a column in table, how to set default value for a column, how to drop a table, how to empty table from data, and how to delete a row from table.

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Renaming Column in Table ALTER TABLE temp CHANGE COLUMN address area VARCHAR(10);

Setting Default Value for a Column: ALTER TABLE temp ADD COLUMN city VARCHAR(100) DEFAULT 'ABC';

Drop Table drop table temp;

Empty Table: TRUNCATE child

Delete a single row from table DELETE FROM child where id = 3;

Delete all rows from table: TRUNCATE child

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LAB 04—DATA COPYING/DELETION Objectives: The objective of this lab is to make students learn how to transfer/copy data from one table to another, how to delete a data from table based on selected criteria, and how to update a specific row in table.

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Transfer/Copy Data from table1 to table2 with same table structure Populating a table (CHILD) by using subset of another table (PARENT) with the same structure. INSERT INTO child SELECT * FROM PARENT;

Delete a single row from table: DELETE FROM temp WHERE id=111; ‘Where’ expression can have either column of the table, but PRIMARY key column is used to avoid unwanted deletion of data. e.g. DELETE FROM temp WHERE name=’Ali’; This will delete all the rows with name Ali.

UPDATE a row in table: First you need to confirm the row you want to update, should exist in the table. e.g. you want to update the row with ID 7. Check if it exists.

SELECT * FROM product_t WHERE productID=7;

If this returns a row. Then the row exists, and you can run the UPDATE query.

UPDATE product_t SET ProductStandardPrice = 775 WHERE ProductID = 7;

This will update the value of the ProductStandardPrice from 800 to 775. 31

LAB 05—AUTO-INCREMENT PRIMARY KEY Objectives: The students will learn how to create an auto-increment primary key. How to insert rows using insert query when auto-increment primary key is defined, and how to initialize the auto-increment primary key for a specified value.

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Creating an AUTO INCREMENT PRIMARY KEY:

CREATE TABLE PERSONS( ID INT NOT NULL AUTO_INCREMENT, NAME VARCHAR (50) NOT NULL, AGE INT, PRIMARY KEY (ID) );

Inserting rows in PERSONS: INSERT INTO PERSONS ( ID , NAME , AGE ) VALUES ( 11 , 'Ali' , 25 ); INSERT INTO PERSONS ( NAME , AGE ) VALUES ( 'Ali' , 25);

This will insert two rows in the table PERSONS, Note that we gave ‘ID’ for the first row i.e. 11 and we did not give any ID for the second row. And it automatically incremented the next row ID based on the maximum ID in the rows already inserted. In the next row the ID will be automatically inserted as 12.

Start Auto Increment with user specified value : ALTER TABLE PERSONS AUTO_INCREMENT = 100;

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After the table is altered for its auto increment value, Insert another record in the table.

INSERT INTO persons ( name , age ) VALUES ( 'Ahmed' , 32 );

The ID of the next row inserted starts from 100 , as altered.

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LAB 06—DATABASE INDEXES Objectives: Students will learn the benefits of creating indexes on database tables, how to create indexes on table fields, and how to drop indexes.

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Creating Indexes :  

Indexes are created in RDBMS to provide rapid and sequential access to base table data. Indexes are usually be created both for primary and secondary keys and both single and concatenated (multiple column keys).

Example: To see the structure of a table we use DESCRIBE command DESCRIBE CUSTOMER_T; /* below command create index */ CREATE INDEX Name_IDX ON CUSTOMER_T (CUSTOMERNAME) ;

To see the structure of a table we use DESCRIBE command DESCRIBE CUSTOMER_T;

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Drop Indexes : To remove index on the customer name in the table. DROP INDEX Name_IDX ON CUSTOMER_T; And describe table to see the index dropped.

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LAB 07—CREATE INDEX ON FOREIGN KEYS Objectives: Students will understand the relation of indexes with a table’s foreign keys. Students will learn how to create indexes on foreign key, and how to drop a foreign key index

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Creating index on foreign key : Create two tables:

CREATE TABLE MASTER( MID VARCHAR(5) PRIMARY KEY, TYPE VARCHAR(10) ); CREATE TABLE DETAIL( DIDT VARCHAR(5) PRIMARY KEY, DES VARCHAR(50), MID VARCHAR(5) );

Add foreign key: ALTER TABLE DETAIL ADD FOREIGN KEY (MID) REFERENCES MASTER(MID);

And drop foreign key: ALTER TABLE DETAIL DROP FOREIGN KEY your_fk_name;

Even after dropping the foreign key, the index still resides and has to be dropped manually, by DROP INDEX MID ON DETAIL;

CONCLUSION: When we create a foreign key in a table, the index is made automatically on the foreign key attribute. When we drop a foreign key, the index does not automatically delete, and we have to delete the index manually.

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LAB 08—SELECT CLAUSE IN DETAIL Objectives: The objective of this lab is to teach student various clauses of SELECT statement. Students will learn about the two special keywords used in select clause.

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Clauses of the SELECT Statement: SELECT: lists the columns (including expressions involving columns i.e. age+10) from base tables, derived tables, or views to be projected into the table that will be the result of the command. FROM: Identifies the tables, derived tables, or views from which columns will be chosen to appear in the result table and include the tables, derived tables, or views needed to join tables to process the query. WHERE: Includes the conditions (Boolean expression) for row selection within the items in the FROM clause and the conditions between tables, derived tables, or views for joining.

Example: Which products have a standard price of less than $275. SELECT * FROM PRODUCT_T WHERE ProductStandardPrice<275;

Two Special Keywords used in SELECT: Two special keywords used in SELECT along with list of columns to display 1. DISTINCT 2. *

DISTINCT: If the user does not wish to see duplicate rows in the result. Example: First run simple query: SELECT PRODUCTDESCRIPTION FROM PRODUCT_T; And count how many rows are returned. (8 rows are returned). Next, run query:

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SELECT DISTINCT PRODUCTDESCRIPTION FROM PRODUCT_T;

And count number of rows returned (7 rows are returned). Duplicate rows are removed from the results (that was ‘Computer Desk’).

*: Retrieves rows for all columns in the table. e.g. SELECT * FROM PRODUCT_T;

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LAB 09—CREATING ALIAS IN DATABASE Objectives: Student will learn how to create a table alias, and a table’s field alias.

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Using Alias in SELECT Statement: Advantage: Using alias make the column names more readable in a select query. Moreover, we can rename a table column name, or a table name, to a new name of our choice in the select query. However, using alias does not change anything in actual table’s structure, it is just used for data reading/presentation from database. The simple query without alias will be: SELECT CUSTOMER_T.CUSTOMERNAME, CUSTOMER_T.CUSTOMERADDRESS FROM CUSTOMER_T WHERE CUSTOMER_T.customerName='Home Furnishings'

Example for Alias: What is the address of the customer named ‘Home Furnishings’? Use an alias, Name, for the customer name.

SELECT CUST.customerName AS CNAME , CUST.CUSTOMERADDRESS AS ADDRESS FROM CUSTOMER_T AS CUST WHERE CUST.customerName='Home Furnishings';

This returns the columns with their alias names, i.e. Name for CusomterName and Address for CustmerAddress.

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LAB 10—SORTING THE DATA Objectives: Students will learn how to sort table data using ORDER BY clause.

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Rearranging column Order in SELECT Query: While creating new table, it is not necessary to create columns in a table in a specific order. Because, we can select data from table in any order we like, by placing the columns in different orders in select query. The below query will return the data in the original order of columns as they were appearing in the actual table (the order in which they were appearing when table was created). SELECT * FROM PRODUCT_T;

Now we want to change the order of columns in the retrieved record in the next query. Query: List the unit price, product name and product ID for all products in the product table, in the same order as given in this statement. SELECT ProductStandardPrice, ProductDescription, ProductID FROM PRODUCT_T;

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LAB 11—USING EXPRESSIONS AND FUNCTIONS Objectives: Students will learn how to use expressions and functions in select queries.

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Using Expressions: Query: What are the standard price and standard price if increased by 10% for every product.

SELECT ProductStandardPrice, ProductStandardPrice*1.1 AS IncreasedBy10 FROM PRODUCT_T;

Returns two columns, one the ProductStandardPrice and the other column with the price increased by 10% and its alias name as IncreasedBy10. (Multiplying 1.1 is equivalent to calculating 10% and adding it to Product Price)

Using Functions: Mathematical:

MIN, MAX, COUNT, SUM, ROUND, MOD, AVG

String:

LOWER(): To change all string characters in lower case. UPPER(): To change all string characters in upper case. INITCAT(): To change only an initial letter to capital CONCAT(): To Concatenate two strings

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SUBSTR(): To isolate character. Used to find a substring in a given string. COALESCE() : Finding the first positions of not null values in a list of columns Date

ADDDATE() : Sum two dates CURDATE(): Return current date DAY() : Given date as input, this function returns the DAY on that date MONTH(): Given date as input, this function returns MONTH on that date YEAR(): Given date as input, this function returns YEAR on that date.

Analytical

TOP() : find the top n values in a set, e.g. top 5 customers by total annual sales

These are only basic functions, search more functions regarding your need on MySQL website. Query: What is the average standard price for all products in inventory? SELECT AVG (ProductStandardPrice) AS AveragePrice FROM PRODUCT_T;

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LAB 12—BUILT-IN FUNCTIONS Objectives: Students will understand the use of some of the built-in functions, such as COUNT, MIN, and MAX.

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COUNT : Returns single row Query: How many different items where ordered number 1004? SELECT COUNT(*) FROM ORDERLINE_T WHERE ORDERID=1004;

Query: How many different items were ordered on order number 1001, and what are they?

SELECT ProductID, COUNT(*) FROM ORDERLINE_T WHERE ORDERID=1001;

This query should return error, because count returns only one row , though we are selecting multiple rows for productID. It will return error in SQL Server or Oracle, but for MySQL query returns the 1st productID along with count as the query result.

Difference between COUNT(*) and COUNT(ColumnName) The following query will not count nulls in count. SELECT COUNT(ProductID) FROM Product_T;

The following query will count nulls in count. SELECT COUNT(*) FROM PRODUCT_T;

Query: Display for each product the difference between its standard price and the overall average standard price of all the products. SELECT ProductStandardPrice, ProductStandardPrice - (SELECT AVG(ProductStandardPrice) 51

AS PriceAvg FROM PRODUCT_T) AS Difference FROM PRODUCT_T ;

The Difference here is a derived attribute from column ProductStandardPrice. Query: Alphabetically, what is the first product_name in the product table?

SELECT MIN(ProductDescription) FROM PRODUCT_T;

The MIN() function is used for numeric values as well as string values, but if there is a string starting with numeric value then the numeric value of the string will be used for comparison (while to rest of the string will be truncated). If instead, we use MAX function, it will give preference to string value, and string starting with highest alphabet position will be return (ignoring the string starting with numeric value)

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LAB 13—NULL VALUES Objectives: Students will learn the work of various comparison operators, and the use of NULL keyword.

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Using Comparison Operators Query: Which orders have been placed since 10/24/2010. SELECT ORDERID , ORDERDATE FROM ORDER_T WHERE ORDERDATE>'2010-10-24';

Query: What furniture does Pine View carry that is not made of Cherry? SELECT ProductDescription, ProductFinish FROM PRODUCT_T WHERE ProductFinish!='Cherry';

Using NULL Values -Columns that are defined without the ‘NOT NULL’ clause may be empty (due to space inside cell). -NULL value means a column is missing a value, the value is not zero, or blank, or any special code – there is simply NULL value. -The functions may produce different results where NULL values are present than when a column has a value of zero. Query : Display all customers for whom we do not know their Postal Code.

/*below query returns all rows for which CustomerPostalCode contains NULL value*/ SELECT * FROM CUSTOMER_T WHERE CustomerPostalCode IS NULL;

/*below query returns all rows for which CustomerPostalCode does not contains NULL value*/

SELECT * FROM CUSTOMER_T WHERE CustomerPostalCode IS NOT NULL;

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LAB 14—LOGICAL OPERATORS Objectives: Students will learn different types of logical operators, and how they are used to filter data in select queries. The use of DISTINCT operator will be also be discussed.

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Using Boolean Operators (Logical Operators): -

AND: Joins two or more conditions and return results only when all conditions are true. OR: Joins two or more conditions and returns results when at least one condition is true. NOT: Negates an expression.

Order of Preference: If multiple Boolean operators are used in an SQL statements, NOT is evaluated first then AND , then OR. Query: List Product Name, Finish, and Standard Price for all desks and all tables that cost more than $300 in the product table. SELECT ProductDescription, ProductFinish, ProductStandardPrice FROM PRODUCT_T WHERE (ProductDescription LIKE '%Desk%' OR ProductDescription LIKE '%Table%' ) AND ProductStandardPrice > 300.00 ;

The LIKE operator is used to search for a specified pattern in a column. % before the string acts as a wild card that anything can appear before the string, but should end with the string. Vice versa % after the string acts as a wild card that anything can appear after the string, but should start with the string. If % is added before and after the string, than the string can appear as a sub-string in a string, either in start, mid, or end.

Expression

Column Value

Returns

LIKE %Desk

Big Desk

True

LIKE Desk%

Desk Shop

True

LIKE %Desk%

Blue Desk Shop

True

LIKE %Desk

My Desk Shop

False

LIKE Desk%

Big Desk Shop

False

Using Ranges for Qualification: Query: Which product in the product table has a standard price between $200 and $300. 56

SELECT ProductDescription, ProductFinish, ProductStandardPrice FROM PRODUCT_T WHERE ProductStandardPrice >= 200.00 AND ProductStandardPrice <= 300.00 ;

Query: Which product in the product table has a standard price between $200 and $300. SELECT ProductDescription, ProductFinish, ProductStandardPrice FROM PRODUCT_T WHERE ProductStandardPrice BETWEEN 200.00 AND 300.00 ;

Using DISTINCT values: Query: What Order numbers are included in the OrderLine table? SELECT OrderID FROM OrderLine_t;

If we are interested only to see which order IDs are appearing rather than how many times they are appearing we will use DISTINCT.

Query: What are distinct order numbers included in orderline table?

SELECT DISTINCT OrderID FROM OrderLine_t;

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LAB 15—UNDERSTANDING IN AND NOT IN Objectives: The objective of this lab is to make students understand the two very important keywords in SQL that are IN and NOT IN, and how to sort data using ORDER BY clause.

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Using IN and NOT IN Lists: To match a list of values. Query: List all customers who live in warmer states. SELECT CustomerName, CustomerCity, CustomerState FROM Customer_t WHERE CustomerState IN(‘FL’ , ‘CA’ , ‘HI’ ,’TX’);

Sorting Results: The ORDER BY Clause ORDER BY: Sorts the final results rows in ascending or descending order. GROUP BY: Groups rows in an intermediate results table were the values in those rows where same for one or more columns. HAVING: Can only be used following a GROUP BY and acts as a secondary WHERE clause, returning only those groups that meet a specified condition. Query: List Customer, City, and State for all customers in the Customer table whose address is Florida, Texas, California, or Hawaii. List the customers alphabetically by state and alphabetically by customer within state. SELECT CustomerCity, CustomerState FROM CUSTOMER_T WHERE ADDRESS IN(‘FL’ , ‘CA’ , ‘HI’,’TX’) ORDER BY CustomerState ,CustomerName; Column names can also be given as its column number i.e. 3, 1. SELECT CustomerName, CustomerCity, CustomerState FROM Customer_T WHERE CustomerState IN ('FL' , 'TX' , 'CA', 'HI') ORDER BY 3 , 1 ;

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LAB 16—THE USE OF “LIMIT” OPERATOR Objectives: The students will understand the benefit and use of LIMIT operator.

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Using LIMIT : LIMIT is used to limit to limit/constraint the number of results returned, or to give a range of rows to return. LIMIT 5: returns 5 rows. LIMIT 2, 3: will skip first 2 rows, and return the next 3 rows. SELECT CustomerName, CustomerCity, CustomerState FROM Customer_T WHERE CustomerState IN ('FL' , 'TX' , 'CA', 'HI') ORDER BY 3 , 1 LIMIT 3, 5;

This will skip the first 3 rows and return next 5 rows.

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LAB 17—GROUP BY AND HAVING CLAUSE Objectives: In this lab, students will learn the use of GROUP BY and HAVING clause.

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Categorizing Results: The GROUP BY Clause: GROUP BY is useful when paired with aggregate functions such as SUM or COUNT. GROUP BY divides a table into subsets (by group); then aggregate function can be used to provide summary information for that group. The single value returned by the previous aggregate function examples is called scalar aggregate. When aggregate functions are used in a GROUP BY clause and several values are returned, they are called vector aggregate. Query: Count the number of customers with addresses in each state.

SELECT CustomerState, COUNT(CustomerState) FROM Customer_T GROUP BY CustomerState;

The next query is ordering results by first preference to CustomerState, and second preference to CustomerCity SELECT CustomerState, CustomerCity, COUNT(CustomerCity) FROM Customer_T GROUP BY CustomerState, CustomerCity;

It is also possible to nest groups within groups; the same logic is used when sorting multiple columns.

Query: Count the number of customers with addresses in each city to which we ship. List the cities by State. WHERE is cannot be used with GROUP BY. HAVING is used with GROUP BY.

Qualify Results by Categories: The HAVING clause acts like a WHERE clause, but it identifies groups, rather than rows, that meet a criterion. Before, we usually see a HAVING clause following by a GROUP BY. 63

Query: Find only states with more than one customer.

SELECT CustomerState, COUNT (CustomerState) FROM Customer_T GROUP BY CustomerState HAVING COUNT (CustomerState) > 1;

To include more than one condition in the HAVING Clause, use AND, OR, and NOT. Query: List, in alphabetical order, the product finish and the average standard price for each finish for selected finishes having an average standard price less than 750. SELECT ProductFinish, AVG(ProductStandardPrice) FROM Product_t WHERE ProductFinish IN ( 'Cherry', 'Natural Ash', 'Natural Maple', 'White Ash') GROUP BY ProductFinish HAVING AVG(ProductStandardPrice) <750 ORDER BY ProductFinish;

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LAB 18—DEFINING VIEWS Objectives: The students will understand the basics of views and how to define views.

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Using and Defining Views: The purpose of a view is to simplify query commands, but a view may also improve data security

and significantly enhance programming consistency and productivity for a database. Query: What are the data elements necessary to create an invoice for a customer? Save this query as a view named Invoice_v. CREATE VIEW Invoice_v AS SELECT Customer_T.CustomerID, CustomerAddress, Order_T.OrderID, Product_T.ProductID, ProductStandardPrice, OrderedQuantity FROM Customer_T, Order_T, OrderLine_T, Product_t WHERE Customer_T.CustomerID = Order_T. CustomerID AND Order_T.OrderID = OrderLine_T.OrderID AND Product_T.ProductID = Orderline_T.ProductID;

Query: What are the data elements necessary to create an invoice for number 1004? SELECT CustomerID, CustomerAddress, ProductID, OrderedQuantity FROM Invoice_V WHERE OrderID=1004;

Query: What is the total values of orders placed for each furniture product ? CREATE VIEW OrderTotals_V AS SELECT ProductID, SUM(ProductStandardPrice * OrderedQuantity) as Total FROM Invoice_V GROUP BY ProductID;

Query: List all furniture products that have ever had a standard price over $300. CREATE VIEW ExpensiveStuff_V AS SELECT ProductID, ProductDescription, ProductStandardPrice FROM Product_t WHERE ProductStandardPrice > 300;

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LAB 19—QUERIES INVOLVING MULTIPLE TABLES Objectives: This lab will teach the students how to write queries on multiple tables, how to use INNER JOIN.

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Processing Multiple Tables: Equi-Join: A join in which the joining condition is based on equality between the values in the common columns. Common columns appear (redundantly) in the result table.

Query: What are the customer IDs and Names of all customers along with the order id for all the orders that are placed? SELECT Customer_T.CustomerID , Order_T.CustomerID, CustomerName, OrderID FROM Customer_T, Order_T WHERE Customer_T.CustomerID = Order_T.CustomerID ORDER BY OrderID;

INNER JOIN….ON are used to establish an equi-join in the FROM clause.

Query: What are the Customer ID and names of all customers, along with the Order IDs for all the orders they have placed? SELECT Customer_t.customerid , order_t.customerid, CustomerName, OrderID FROM customer_t INNER JOIN Order_T ON Customer_t.customerid = Order_T.customerid ORDER BY OrderID;

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LAB 20—DIFFERENT TYPES OF JOINS Objectives: Students will learn how to use different types of joins, left outer join, right outer join

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Outer Join: A join in which rows that do not have matching value in common columns are nevertheless included in the results table. Null values appear in columns where there is no match between tables. Example use: In Order_T table come customers’ orders are appearing. There are some customers in Customer_T who have not placed any order. Due to that qui-join shown previously do not include all the customer shown in Customer_T. The organization may be very interested in identifying those customers who have not placed orders. It might want to contact them to encourage new orders, or it might be interested in analyzing the customers to know why they are not ordering. Using an outer join produces this information.

Left OUTER Join Query: List customer name, identification number, and order number for all customers listed in the customer table. Include the customer identification number and name even if there is no order available for that customer.

SELECT Customer_t.Customerid, Customername, Orderid FROM Customer_t LEFT OUTER JOIN Order_t ON Customer_t.CustomerID = Order_t.customerid;

Query: List customer name , identification number, and order number for all orders listed in the order table. Include the order number, even if there is no customer name, and identification number available. SELECT customer_t.CustomerID, CustomerName, OrderID FROM Customer_T RIGHT OUTER JOIN Order_t ON Customer_t.CustomerID = Order_t.CustomerID;

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This query will also return the rows in which the foreign key column does not exist i.e. NULL, for any row

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LAB 21—SELF JOIN Objectives: The objective of this lab is to teach how to use SELF JOIN, and running query involving 4 tables.

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Sample join Involving four tables: Query: Assemble all information necessary to create an invoice for order number 1006. SELECT Customer_t.CustomerID, CustomerName , CustomerAddress, CustomerCity, CustomerState, CustomerPostalCode, Order_t.OrderID, OrderedQuantity, ProductDescription, ProductStandardPrice, (OrderedQuantity * ProductStandardPrice) AS price FROM Order_t, Customer_t, Orderline_t, Product_t WHERE Customer_t.Customerid = Order_t.CustomerID AND Orderline_T.orderID = order_t.orderid AND orderline_t.ProductID = product_t.productid AND Order_t.OrderID = 1006;

Self Join: There are times when a join requires matching rows in a table with other rows in that same table – that is joining a table with itself.

Query: What are the employee ID and name of each employee, and the name of his/her supervisor (label the name of supervisor’s name with manager)? SELECT E.EmployeeID, E.EmployeeName, M.EmployeeName AS Manager FROM Employee_T E, Employee_T M

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WHERE E.EmployeeSupervisor = M.EmployeeID;

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LAB 22—SUBQUERIES Objectives: The purpose of this lab is to familiarize students with how to call a query within other query to make a sub-query, and how to write efficient sub-queries.

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Subqueries The preceding SQL examples illustrate one of the two basic approaches for joining two tables: the joining technique. SQL also provides the subquery technique, which involves placing an inner query (SELECT . . . FROM . . . WHERE) within a WHERE or HAVING clause of another (outer) query. The inner query provides a set of one or more values for the search condition of the outer query. Such queries are referred to as subqueries or nested subqueries. Subqueries can be nested multiple times. Subqueries are prime examples of why SQL is a set-oriented language. Query: (Not Subquery) What are the name and address of the customer who placed order number 1008? SELECT CustomerName, CustomerAddress, CustomerCity, CustomerState, CustomerPostalCode FROM Customer_T, Order_T WHERE Customer_T.CustomerID = Order_T. CustomerID AND OrderID = 1008;

Query (Sub-query): What are the name and address of the customer who placed order number 1008? SELECT CustomerName, CustomerAddress, CustomerCity,CustomerState, CustomerPostalCode FROM Customer_T WHERE Customer_T.CustomerID = (SELECT Order_T.CustomerID FROM Order_T WHERE OrderID = 1008); Query: What are the names of customers who have placed orders?

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SELECT CustomerName FROM Customer_T WHERE CustomerID IN (SELECT DISTINCT CustomerID FROM Order_T);

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LAB 23—IN, NOT IN, EXISTS, NOT EXISTS Objectives: This lab is intended to introduce students with some powerful keywords of SQL, and how to make their good use to reduce query size.

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Using the NOT IN qualifier: Query: Which customers have not placed any orders for computer desks?

SELECT CustomerName FROM Customer_T WHERE CustomerID NOT IN (SELECT CustomerID FROM Order_T, OrderLine_t, Product_T WHERE OrderLine_t.OrderID = Order_t.OrderID AND OrderLine_T.ProductID = Product_t.ProductID AND ProductDescription = 'Computer Desk');

Using EXISTS and NOT EXISTS: EXISTS will take value of true in the sub query return an intermediate result table that contains one or more rows (i.e. a non-empty row set) and false if no rows are returned (i.e. an empty set). NOT EXISTS: will take a value of true if no rows are returned and false if one or more rows are returned

EXISTS versus IN and NOT EXISTS versus NOT IN. WE use EXISTS when we just want to check whether the sub query returns a non-empty set (i.e we don’t care what is in the set, just whether it is empty), and we use IN when we need to know what values are in the. IN and NOT IN return a set of values from only one column which can be then compared to one column in the outer query. EXISTS and NOT EXISTS return only true or false value depending on whether there are any rows in the answer table of the inner query or sub query.

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Query: What are the order IDs for all orders that have included furniture finished in Naturals ash? SELECT DISTINCT OrderID FROM OrderLine_T WHERE EXISTS (SELECT * FROM Product_T Where ProductID = Orderline_t.ProductID AND ProductFinish = 'Natural Ash' );

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LAB 24—DERIVED TABLES AND SUB-QUERIES Objectives: The purpose of this lab is to familiarize students with queries involving derived tables, and the correlated sub queries.

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Correlated Subqueries: Correlated sub queries use the result of outer query to determine the processing of the inner query. In this case, the inner query must be computed for each outer row. Example Correlated Subquery: Query: List the details about the product with the highest standard price; SELECT ProductDescription, ProductFinish, ProductStandardPrice FROM Product_t PA WHERE PA.ProductStandardPrice > ALL (SELECT ProductStandardPrice FROM Product_t PB WHERE PB.ProductID != PA.ProductID)

The word ALL, which must follow a comparison operator, means “return TRUE if the comparison is TRUE for ALL of the values in the column that the subquery returns.

Using Derived Tables: Subquery may also be used in the FROM clause to create a temporary derived table (or SET) that is used in the query. Creating a derived table that has an aggregate value in it, such as MAX, AVG, or MIN, allows the aggregate to be used in the where clause.

Query: Show the product description , product standard price, and overall average standard price for al products that have a standard price that is higher than average standard price.

SELECT ProductDescription, ProductStandardPrice, AvgPrice FROM (SELECT AVG(ProductStandardPrice) AvgPrice FROM Product_t) tempTable, Product_t WHERE ProductStandardPrice > AvgPrice;

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LAB 25—UNION OPERATOR & TYPE CONVERSION Objectives: The purpose of this lab is to brief students about how to use the UNION operator to join results from different queries, and how we can use type conversion in MySQL.

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Union Operator: Combining Queries: The UNION clause is used to combine the output (i.e. union the set of rows from multiple queries together into a single result table. To use the UNIION clause we each query involved must output the same number of columns , and they must be of compatible data types. SELECT C1.CustomerID, CustomerName, OrderedQuantity, ' Largest Quantity' AS Quantity FROM Customer_t C1, Order_t O1, OrderLine_t Q1 WHERE C1.CustomerID = O1.CustomerID AND O1.OrderID = Q1.OrderID AND OrderedQuantity= (SELECT MAX(OrderedQuantity) FROM OrderLine_t) UNION SELECT C1.CustomerID, CustomerName, OrderedQuantity, ' Smallest Quantity' AS Quantity FROM Customer_t C1, Order_t O1, OrderLine_t Q1 WHERE C1.CustomerID = O1.CustomerID AND O1.OrderID = Q1.OrderID AND OrderedQuantity= (SELECT MIN(OrderedQuantity) FROM OrderLine_t) ORDER BY 3;

Query: The following query determines the customer(s) who has in a given line item purchases the largest quantity of any Pine Valley product and the customer(s) who has in a given line item purchased the smallest quantity and returns the results in the table. INTERSECT: An INTERSECT is simply an inner join where we compare the tuples of one table with those of the other, and select those that appear in both while weeding out duplicates. MINUS: The MINUS operator takes the distinct rows of one query and returns the rows that do not appear in a second result set.

Data Type Conversion: CAST operator us used to control the data type conversion. SELECT CAST(OrderDate as CHAR) FROM Order_T;

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LAB 26—CONDITIONAL EXPRESSION AND TRIGGER Objectives: This lab will introduce students with conditional expressions, as well as how we can define and use triggers in MySQL.

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Conditional Expressions: IF-THEN-ELSE CASE Keyword

Query: SELECT CASE WHEN ProductLineID=1 THEN ProductDescription ELSE '###' END AS ProductDescription FROM Product_t;

Triggers A named set of SQL statements that are triggered automatically when a data modification (i.e., INSERT, UPDATE, DELETE) occurs or if certain data definitions are encountered. If a condition stated within a trigger is met, then a prescribed action is taken. Triggers are used when you need to perform, under specified conditions, a certain action as the result of some database event (e.g., the execution of a DML statement such as INSERT, UPDATE, or DELETE or the DDL statement ALTER TABLE). Thus, a trigger has three parts—the event, the condition, and the action—and these parts are reflected in the coding structure for triggers. Command to see the triggers currently in database; show triggers;

Now to understand trigger, create a new table named: PriceUpdates_T use pineview;

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create table PriceUpdates_T ( ProductID int, ProductDescription varchar(50), UpdateDate DATE, NewPrice decimal(6,2) )

Now we write the trigger code as follows, that will create a trigger with name: StandardPriceUpdate use pineview;

CREATE TRIGGER StandardPriceUpdate AFTER UPDATE ON Product_T FOR EACH ROW INSERT INTO PriceUpdates_T VALUES (NEW.ProductID, NEW.ProductDescription, curdate(), NEW.ProductStandardPrice);

To see our newly created trigger use following command show triggers; Now the following command will automatically execute (trigger) the trigger “StandardPriceUpdate” update product_t set productstandardprice=210 where productid=3;

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After the above command is run, check the data in PriceUpdates_T table SELECT * FROM priceupdates_t;

You will see a new row is inserted in the PriceUpdates_T table. How it happened? The trigger code “StandardPriceUpdate” states that whenever there is an update in Product_T table, the updated row(s) fields will be automatically inserted into the PriceUpdates_T as new rows. That’s why we are seeing new row inserted into PriceUpdates_T table. FOR EACH ROW means that, the new row in PriceUpdates_T will be inserted for each updated row, e.g., the following query updates two rows in the product_t table. update product_t set ProductStandardPrice=333 where productid in (5,6);

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LAB 27—INTRODUCTION TO STORED PROCEDURES Objectives: This lab introduces the stored procedures and discuss several examples of how effectively can we use stored procedures in MySQL.

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Stored Procedures: A collection of procedural and SQL statements that are assigned a unique name within the schema and stored in the database. A procedure may have input parameters, output parameters, and parameters that are both input and output parameters. The following procedure performs three tasks. It inserts a new field in Product_T table named “SalePrice”. It updates SalePrice for ProductStandardPrice >= 400 It updates SalePrice for ProductStandardPrice < 400 CREATE PROCEDURE `ProductLineSale` () BEGIN

ALTER TABLE Product_T ADD COLUMN SalePrice decimal(6,2);

UPDATE Product_T SET SalePrice = .90 * ProductStandardPrice WHERE ProductStandardPrice >= 400;

UPDATE Product_T SET SalePrice = .85 * ProductStandardPrice WHERE ProductStandardPrice < 400;

END

To execute a stored procedure we use the following command call ProductLineSale();

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LAB 28—STORED PROCEDURE – SINGLE INPUT Objectives: The purpose of this lab is to make students learn how we can pass a single argument to stored procedures.

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STORED PROCEDURE WITH A SINGLE INPUT PARAMETER The following stored procedure takes a single int value as input and returns a limited set of records based on the provided input parameter.

CREATE PROCEDURE `get_Records` (total INT) BEGIN SELECT * FROM Product_T LIMIT total; END

Use the above procedure, the following code will return just 2 records call get_Records(2)

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LAB 29—STORED PROCEDURES – INPUT/OUTPUT Objectives: In this lab students will lab, how can pass single input and output single value from stored procedures.

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STORED PROCEDURE WITH A SINGLE INPUT and A SINGLE OUTPUT PARAMETER The following stored procedure takes as input a single parameter and outputs result into a single parameter. For the output parameter, we use OUT keyword CREATE PROCEDURE `get_count`(mynum INT, OUT outnum INT) BEGIN SELECT count(productid) into outnum from product_t where productid > mynum; END

To call the above procedure we use code CALL get_count(3,@outnum); select @outnum; The above procedure is returning count of records into outnum, and only those records’ count is returned whose productid is greater than 3.

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LAB 30—STORED PROCEDURE RETURNING VALUES Objectives: Students will learn how we can define and use a stored procedure that is able to return multiple values, provided with an input value.

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STORED PROCEDURE WITH A SINGLE INPUT PARAMETER and TWO OUTPUT PARAMETERS CREATE PROCEDURE `get_multiple_values`(prodid INT, OUT proddesc VARCHAR(50), OUT price decimal(6,2)) BEGIN SELECT ProductStandardPrice into price from product_t where productid = prodid; SELECT ProductDescription into proddesc from product_t where productid = prodid; END To call the above procedure we use code: CALL get_multiple_values(3,@proddesc, @price); select @proddesc, @price;

Here, the above procedure is returning values of product description and product standard price for a provided productid=3.

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LAB 31—USING MYSQL FUNCTIONS Objectives: In this lab, students will learn how to define, and use functions in MySQL, and how to pass arguments and return values from functions.

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MySQL FUNCTIONS A function returns one value and has only input parameters. You have already seen the many built-in functions included in SQL, such as MAX, MIN, CEILING, FLOOR, SQRT, etc. The following function returns takes one value as input and returns a single value. CREATE FUNCTION `my_function` (myinput INT) RETURNS INTEGER BEGIN declare temp int; SELECT COUNT(*) into temp from Product_T where productid>myinput; RETURN temp; END

To call this function we use code select my_function(3);

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LAB 32—CONNECTING MYSQL WITH PHP Objectives: Purpose of this lab is to create a small application connecting PHP with MySQL. Creating PHP forms to insert data into database, delete data, update data, and select data from database.

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CONNECTING PHP with MySQL Make sure you have “pineview” database successfully configured in your MySQL server / wamp. Follow the following steps. Run wampserver, and make sure that phpmyadmin is opening and running fine. If not, there might be some port issues, change port of apache server to 8080. Or quit skype and re-return the wampserver, as skype uses the same port as wampserver. Step-1: In “www” folder of your wampserver, create a new folder with name: “myproject”. Step-2: Uncheck the following option from “Folder and Search” options of your PC “hide file extensions for known file type”, and click on apply/ok. Step-3: In “myproject” folder create three files, namely “index.php”, “selectdata.php”, and “updatedata.php”. Step-4: Using notepad++, write the following code in “index.php”. index.php

Home

Show Record

Update Data

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THIS IS HOME PAGE

Step-5: Write following code in “selectdata.php”. Make sure you correctly set values shown in red font below as per your system configuration. (Means these values may be changed in your system.) selectdata.php

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Update Data

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$servername = "localhost"; $username = "root"; $password = "ciit"; // set this field "" (empty quotes) if you have not set any password in mysql $dbname = "pineview";

try { $conn = new PDO("mysql:host=$servername;dbname=$dbname", $username, $password); // set the PDO error mode to exception $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

echo "Connection successful"; ?>


foreach($conn->query('SELECT * FROM product_t') as $row) { ?> 102

ProductID	ProductLineID	ProductDescription	ProductFinish	ProductStandardPrice

" . $e->getMessage(); }

$conn = null; ?> 103



Step-6: Create file “updatedata.php” and put following code in that. updatedate.php

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Update Data

try { 104

$conn = new PDO("mysql:host=$servername;dbname=$dbname", $username, $password); // set the PDO error mode to exception $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

echo "Connection successful";

//

$sql = "update product_t set productdescription='new table' where productid=3";

if( isset($_POST['btn']) ) {

$txt1 = $_POST['txt1']; $txt2 = $_POST['txt2']; $txt3 = $_POST['txt3']; $txt4 = $_POST['txt4']; $txt5 = $_POST['txt5'];

//echo $txt1 . " " . $txt2 . " " . $txt3 . " " . $txt4 . " " . $txt5;

$sql = "insert into product_t (ProductID, ProductLineID, ProductDescription, ProductFinish, ProductStandardPrice) values ($txt1, $txt2, '$txt3', '$txt4', $txt5)";

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// use exec() because no results are returned

$conn->exec($sql); echo "\nTable product_t updated successfully"; } } catch(PDOException $e) { echo $sql . "
" . $e->getMessage(); }

$conn = null; ?>

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ProductID
ProductLineID
ProductDescription
ProductFinish
ProductStandardPrice
Save Record

Step-7: Test your application by giving command: http://localhost/myproject/index.php or if your apache server is using port 8080 then, http://localhost:8080/myproject/index.php As a final note, instead of repeating the same data connection code in each file again and again, you can put it in one file and call that file in your remaining files. For example, create a new file named: “opendb.php”, and add following code in that: opendb.php
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try { $conn = new PDO("mysql:host=$servername;dbname=$dbname", $username, $password); // set the PDO error mode to exception $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

echo "Connection successful"; } catch(PDOException $e) { echo $sql . "
" . $e->getMessage(); }

?>

Now, as a sample code, you can re-write the selectdata.php file as:

selectdata.php 109

Home

Show Record

Update Data

foreach($conn->query('SELECT * FROM product_t') as $row) { ?> 110

ProductID	ProductLineID	ProductDescription	ProductFinish	ProductStandardPrice

" . $e->getMessage(); }

$conn = null; ?>

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We can see, the database connection code is removed from above file, and we are just including the file that is maintaining the database connectivity. The similar modifications can also be performed in other files.

------- THE END OF LAB MANUAL ----------

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