It select a MySQL database

MySQL Table – Users
+—-+——+
| id | name |
+—-+——+
|  1 | PHP  |
|  2 | ASP  |
|  3 | JSP  |
|  4 | JS  |
|  5 | AS  |
+—-+——+

Example

<?php
mysql_pconnect(“localhost”, “root”, “phpcode”) or die(mysql_error());
mysql_select_db(“database_name”);
echo mysql_result(mysql_query( “SELECT * FROM users”),1);
mysql_close();
?>

Output

2

It returns the value of a field in a recordset

MySQL Table – Users
+—-+——+
| id | name |
+—-+——+
|  1 | PHP  |
|  2 | ASP  |
|  3 | JSP  |
|  4 | JS  |
|  5 | AS  |
+—-+——+

Example

<?php
mysql_pconnect(“localhost”, “root”, “phpcode”) or die(mysql_error());
$db_selected = mysql_select_db(“database_name”);
echo mysql_result(mysql_query( “SELECT * FROM users”),1);
mysql_close();
?>

Output

2

Escapes a string for use in SQL statements

MySQL Table – Users
+—-+——+
| id | name |
+—-+——+
|  1 | PHP  |
|  2 | ASP  |
|  3 | JSP  |
|  4 | JS  |
|  5 | AS  |
+—-+——+

Example
<?php
mysql_pconnect(“localhost”, “root”, “phpcode”) or die(mysql_error());
$db_selected = mysql_select_db(“database_name”);
echo mysql_num_rows(mysql_query( “SELECT * FROM users WHERE name='”.mysql_real_escape_string(“PHP”).”‘”));
mysql_close();
?>

Output
1

It executes a query on a MySQL database

MySQL Table – Users
+—-+——+
| id | name |
+—-+——+
|  1 | PHP  |
|  2 | ASP  |
|  3 | JSP  |
|  4 | JS  |
|  5 | AS  |
+—-+——+

Example
<?php
mysql_pconnect(“localhost”, “root”, “phpcode”) or die(mysql_error());
$db_selected = mysql_select_db(“database_name”);
echo mysql_num_rows(mysql_query( “SELECT * FROM users”));
mysql_close();
?>

Output
5

Ping a server connection or reconnect if there is no connection

MySQL Table – Users

+—-+——+
| id | name |
+—-+——+
|  1 | PHP  |
|  2 | ASP  |
|  3 | JSP  |
|  4 | JS  |
|  5 | AS  |
+—-+——+

Example

<?php
mysql_pconnect(“localhost”, “root”, “phpcode”) or die(mysql_error());
$db_selected = mysql_select_db(“database_name”);
mysql_ping();
echo mysql_num_rows(mysql_query( “SELECT * FROM users”));
mysql_close();
?>

Output

5

It opens a persistent MySQL connection

MySQL Table – Users

+—-+——+
| id | name |
+—-+——+
|  1 | PHP  |
|  2 | ASP  |
|  3 | JSP  |
|  4 | JS  |
|  5 | AS  |
+—-+——+

Example

<?php
mysql_pconnect(“localhost”, “root”, “phpcode”) or die(mysql_error());
$db_selected = mysql_select_db(“database_name”);
echo mysql_num_rows(mysql_query( “SELECT * FROM users”));
mysql_close();
?>

Output

5

It returns number of rows in result

MySQL Table – Users

+—-+——+
| id | name |
+—-+——+
|  1 | PHP  |
|  2 | PHP  |
|  3 | PHP  |
|  4 | PHP  |
|  5 | PHP  |

Example

<?php
mysql_connect(“localhost”, “root”, “phpcode”) or die(mysql_error());
$db_selected = mysql_select_db(“database_name”);
echo mysql_num_rows(mysql_query( “SELECT * FROM users”));
mysql_close();
?>

Output

5

It returns number of fields in result

MySQL Table

+—-+——+
| id | name |
+—-+——+
|  1 | PHP  |
|  2 | PHP  |
|  3 | PHP  |
|  4 | PHP  |
|  5 | PHP  |

Example

<?php
mysql_connect(“localhost”, “root”, “phpcode”) or die(mysql_error());
$db_selected = mysql_select_db(“database_name”);
echo mysql_num_fields(mysql_query( “SELECT * FROM users”));
mysql_close();
?>

Output

2

It lists tables in a MySQL database . Its deprecated

Example

<?php
$conn=mysql_connect(“localhost”, “root”, “phpcode”) or die( mysql_error());
$table = mysql_list_tables (“database_name”);
for ($i=0; $i < mysql_num_rows($table); ++$i) {
echo mysql_result ($table, $i, 0), ‘<br />’;
}
?>

Output

users

It lists MySQL processes

Example

<?php
$conn=mysql_connect(“localhost”, “root”, “phpcode”) or die( mysql_error());
echo “<pre>”;
$process= mysql_list_processes($conn);
while ($row = mysql_fetch_assoc($process)) {
print_r($row);
}
?>

Output

Array
(
[Id] => 1061
[User] => root
[Host] => localhost
[db] =>
[Command] => Processlist
[Time] => 0
[State] =>
[Info] =>
)