Module 3. 1. Review Basic SQL commands: Create Database, Create Table, Insert and Select 2. Connect...

Module 3

1. Review Basic SQL commands: Create Database, Create Table, Insert and Select

2. Connect an SQL Database to PHP

3. Execute SQL Commands in PHP

Standard Query Language

SQL stands for Structured Query Language SQL is a standard language for accessing

databases. MySQL, SQL Server, Access, Oracle,

Sybase, DB2, and other database systems. SQL lets you access and manipulate

databases SQL is an ANSI (American National

Standards Institute) standard

Although SQL is an ANSI (American National Standards Institute) standard, there are many different versions of the SQL language.

However, to be compliant with the ANSI standard, they all support at least the major commands (such as SELECT, UPDATE, DELETE, INSERT, WHERE) in a similar manner.

Note: Most of the SQL database programs also have their own proprietary extensions in addition to the SQL standard!

To build a web site that shows some data from a database, you will need the following:• An RDBMS database program (i.e. MS

Access, SQL Server, MySQL)• A server-side scripting language, like PHP or

ASP• SQL• HTML / CSS

CREATE DATABASE database_name•Eg. Create database friends;

A database most often contains one or more tables. Each table is identified by a name (e.g. "Customers" or "Orders"). Tables contain records (rows) with data.

CREATE TABLE table_name(column_name1 data_type,column_name2 data_type,column_name3 data_type,....)

CREATE TABLE Friends(idnumber int,LastName varchar(255),FirstName varchar(255),Age varchar(255),Gender varchar(255))

Constraints are used to limit the type of data that can go into a table.

Constraints can be specified when a table is created (with the CREATE TABLE statement) or after the table is created (with the ALTER TABLE statement).• NOT NULL• UNIQUE• PRIMARY KEY• FOREIGN KEY• CHECK• DEFAULT

Id_number Lastname Firstname Age Gender

0001 Agcopra Jim 21 M

0002 Agcopra Joseph 26 M

0003 Galamiton Palquincy 21 M

0004 Belono Cyril 22 F

0005 Gener Kathleen 30 F

0006 De Castro Rose Ann 23 F

0007 Castillo Joan Rose 28 F

0008 Llanderal Joan Rey 29 F

0009 Carbonell Andrew 27 M

0010 Roa Bambi Rey 28 M

0011 Agcopra Jason 28 M

The SELECT statement is used to select data from a database.

The result is stored in a result table, called the result-set.

SQL SELECT Syntax•SELECT column_name(s)FROM table_name

and•SELECT * FROM table_name

and•SELECT * FROM table_name WHERE [Conditions]

•Eg. Select * From ekek where lastname = ‘Gargar’;

SELECT * FROM NAMES SELECT Lastname,Firstname From

Names SELECT * FROM Names Where

Lastname = ‘Agcopra’ SELECT * FROM Names Where

Firstname like ‘A%’; Select * From Names Where Age > 25

AND Gender = ‘M’

Standard Query Language

Know your HTMLS Know common PHP Commands and Structures

Master your SQL

1. Check if there is an PHP-SQL connection

2. Use a Database3. Get a Table and Execute Queries4. Extract Data from the Queries.5. Close your Database after use.

<?php

$connection = mysql_connect(‘localhost’,’root’,’password’) or die (‘Unable to Connect’);

if($connection!=NULL){echo "SQL is Connected to PHP";}

mysql_select_db('friends') or die ('Unable to select a database!');

$query = 'Select * FROM names';

$result = mysql_query($query) or die (‘error in query’);

('Error in query: $query. ' . msql_error());

There are 3 different ways to extract data:• Mysql_fetch_row()• Mysql_fetch_assoc()• Mysql_fetch_object()

1] echo "<ol>";2] 3] if(mysql_num_rows($result) > 0)4] {5] while($row =

mysql_fetch_row($result))6] {7] echo "<li> <b>$row[1]</b>,

$row[2] </li>";8] }9] }10]echo "</ol>";

1] echo "<ol>";2] 3] if(mysql_num_rows($result) > 0)4] {5] while($row =

mysql_fetch_assoc($result))6] {7] echo "<li> <b>$row[‘lastname’]</b>,

$row[‘firstname’] </li>";8] }9] }10]echo "</ol>";

1] echo "<ol>";2] 3] if(mysql_num_rows($result) > 0)4] {5] while($row =

mysql_fetch_object($result))6] {7] echo "<li> <b>$row->lastname</b>, $row-

>firstname </li>";

8] }9] }10]echo "</ol>";

mysql_free_result($result);mysql_close($connection);

?>

<?php

$connection = mysql_connect(‘localhost’,’root’,’password’);mysql_select_db('friends') ;$query = 'Select * FROM names';$result = mysql_query($query);echo "<ol>";if(mysql_num_rows($result) > 0)

{while($row = mysql_fetch_row($result))

{echo "<li> <b>$row[1]</b>, $row[2] </li>";}

}echo "</ol>";mysql_free_result($result);mysql_close($connection);

?>

PHP Commands

mysql_connect(a,b,c )a = dbserverb = userc = password

mysql_select_db(a)a = database

mysql_query(a)a = SQL command

mysql_num_rows()Counts the number of rows

$a=mysql_fetch_row(a)

$a=mysql_fetch_assoc()

$a=mysql_fetch_object()

mysql_free_result(a) Mysql_close()

1st Activity for the Semi-Finals

1. Make a Database named DB_31_[your block]

2. Make a Table named Employees• Data Entity and Attributes:• Idnum• Lastname• Firstname• Department (Admin, Logistics, Sales,

Accounting)

• Years• Gender

1st Page:

The Site will Ask for the Lastname

2nd Page:

The Site will Show the Record

Does the

record

exist?

Error Page:

The Site give a feedback

False

True

Show your work on next Tuesday.