MYSQL TUTORIALS - MySQL Where Clause

MySQL Where Clause

Syntax:

Operator	Description	Example
=	Checks if the values of two operands are equal or not, if yes then condition becomes true.	(A = B) is not true.
!=	Checks if the values of two operands are equal or not, if values are not equal then condition becomes true.	(A != B) is true.
>	Checks if the value of left operand is greater than the value of right operand, if yes then condition becomes true.	(A > B) is not true.
<	Checks if the value of left operand is less than the value of right operand, if yes then condition becomes true.	(A < B) is true.
>=	Checks if the value of left operand is greater than or equal to the value of right operand, if yes then condition becomes true.	(A >= B) is not true.
<=	Checks if the value of left operand is less than or equal to the value of right operand, if yes then condition becomes true.	(A <= B) is true.

Syntax:

SELECT field1, field2,...fieldN table_name1, table_name2...
[WHERE condition1 [AND [OR]] condition2.....

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						Example:

root@host# mysql -u root -p password;
Enter password:*******
mysql> use TUTORIALS;
Database changed
mysql> SELECT * from tutorials_tbl WHERE tutorial_author='Sanjay';
+-------------+----------------+-----------------+-----------------+
| tutorial_id | tutorial_title | tutorial_author | submission_date |
+-------------+----------------+-----------------+-----------------+
|           3 | JAVA Tutorial  | Sanjay          | 2007-05-21      |
+-------------+----------------+-----------------+-----------------+
1 rows in set (0.01 sec)

mysql>

						
root@host# mysql -u root -p password;
Enter password:*******
mysql> use TUTORIALS;
Database changed
mysql> SELECT * from tutorials_tbl \
          WHERE BINARY tutorial_author='sanjay';
Empty set (0.02 sec)

mysql>

						Example:

<?php
$dbhost = 'localhost:3036';
$dbuser = 'root';
$dbpass = 'rootpassword';
$conn = mysql_connect($dbhost, $dbuser, $dbpass);
if(! $conn )
{
  die('Could not connect: ' . mysql_error());
}
$sql = 'SELECT tutorial_id, tutorial_title, 
               tutorial_author, submission_date
        FROM tutorials_tbl
        WHERE tutorial_author="Sanjay"';

mysql_select_db('TUTORIALS');
$retval = mysql_query( $sql, $conn );
if(! $retval )
{
  die('Could not get data: ' . mysql_error());
}
while($row = mysql_fetch_array($retval, MYSQL_ASSOC))
{
    echo "Tutorial ID :{$row['tutorial_id']}  <br> ".
         "Title: {$row['tutorial_title']} <br> ".
         "Author: {$row['tutorial_author']} <br> ".
         "Submission Date : {$row['submission_date']} <br> ".
         "--------------------------------<br>";
} 
echo "Fetched data successfully\n";
mysql_close($conn);
?>