Introduction
In this article I describe the PHP MySQLi functions mysqli_num_rows, mysqli_options, mysqli_ping, mysqli_query and mysqli_real_connect. To learn some other MySQLi functions, go to:
- MySQLi Function in PHP: Part 1
- MySQLi Function in PHP: Part 2
- MySQLi Function in PHP: Part 3
- MySQLi Function in PHP: Part 4
- MySQLi Function in PHP: Part 5
- MySQLi Function in PHP: Part 6
- MySQLi Function in PHP: Part 7
- MySQLi Function in PHP: Part 8
- MySQLi Function in PHP: Part 9
PHP mysqli_num_rows() Function
The PHP MySQLi "mysqli_num_rows" function gets the number of rows in a result and this function returns the number of rows in the result set.
Syntax
Parameter in mysqli_num_rows function
The parameter of the function is:
| Parameter |
Description |
| result |
It specifies the result set identifier returned by mysqli_query(), mtsqli_stored_result or mysqli_use_result(). |
Example
An example of the function is:
<?php
$con=mysqli_connect("localhost","root","","mysql");
if(mysqli_connect_errno($con))
{
echo "Falied to connect to MySQL: ".mysqli_connect_error();
}
$qry="SELECT id,name FROM emp";
if($result=mysqli_query($con,$qry))
{
//returns the number of rows in the result set
$rowCount=mysqli_num_rows($result);
printf("Result set has %d rows.",$rowCount);
// For freeinf the result set
mysqli_free_result($result);
print "<h2>MySQL: Data of Emp table</h2>";
$result =mysqli_query($con,"SELECT * FROM emp");
echo "<table border='1'>
<tr>
<th>Id</th>
<th>Name</th>
<th>Salary</th>
</tr>";
while($rowval = mysqli_fetch_array($result))
{
echo "<tr>";
echo "<td>" . $rowval['id'] . "</td>";
echo "<td>" . $rowval['name'] . "</td>";
echo "<td>" . $rowval['salary'] . "</td>";
echo "</tr>";
}
echo "</table>";
}
print "<h2>The above table contains only 8 rows.</h2>";
mysqli_close($con);
?>
Output
![mysqli-num-rows-function-in-php.jpg]()
PHP mysqli_options() Function
The PHP MySQLi "mysqli_options" function sets extra connection options and behavior for a connection and this function returns true on success or false on failure.
Syntax
| mysqli_options(connection,option,value); |
Parameter in mysqli_options function
The parameters of the function are:
| Parameter |
Description |
| connection |
It specifies the MySQL connection to use. |
| options |
It specifies the option to set. |
| value |
It specifies the value for the option. |
Example
An example of the function is:
<?php
$mysqli = mysqli_init();
//set connection options
$mysqli->options(MYSQLI_INIT_COMMAND, "SET AUTOCOMMIT=0");
$mysqli->options(MYSQLI_OPT_CONNECT_TIMEOUT, 5);
//connect to server */
$mysqli->real_connect('localhost', 'root', '', 'mysql');
if (mysqli_connect_errno())
{
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
printf ("Connection: %s\n.", $mysqli->host_info);
$mysqli->close();
?>
Output
![mysqli-options-function-in-php.jpg]()
PHP mysqli_ping() Function
The PHP MySQLi "mysqli_ping" function pings a server connection or attempts reconnection if the connection has gone down and this function returns true on success or false on failure.
Syntax
Parameter in mysqli_ping function
The parameter of the function is:
| Parameter |
Description |
| connection |
It specifies the MySQL connection to use. |
Example
An example of the function is:
<?php
$con=mysqli_connect("localhost","root","","mysql");
if(mysqli_connect_errno($con))
{
echo "Connection Error: ".mysqli_connect_error();
}
if(mysqli_ping($con))
{
echo "Connection has been established successfully.";
}
else
{
echo "Error: ".mysqli_error($con);
}
mysqli_close($con);
?>
Output
![mysqli-ping-function-in-php.jpg]()
PHP mysqli_query() Function
The PHP MySQLi "mysqli_query" function performs a query on the database and this function return a mysqli_result object on the SELECT, SHOW, DESCRIBE or EXPLAIN queries and for the other successful queries it will return true otherwise it returns false.
Syntax
| mysqli_query(connection,query,resultMode); |
Parameter in mysqli_query function
The parameters of the function are:
| Parameter |
Description |
| connection |
It specifies the MySQL connection to use. |
| query |
It specifies a query string. |
| resultMode |
It specifies a constant. |
Example
An example of the function is:
<?php
$con=mysqli_connect("localhost","root","","mysql");
if(mysqli_connect_errno($con))
{
echo "Connection Error: ".mysqli_connect_error();
}
$qry="SELECT * FROM emp";
$result =mysqli_query($con,$qry);
print "<h2>MySQL: Emp table Data</h2>";
echo "<table border='1'>
<tr>
<th>Id</th>
<th>Name</th>
<th>Salary</th>
</tr>";
while($rowval = mysqli_fetch_array($result))
{
echo "<tr>";
echo "<td>" . $rowval['id'] . "</td>";
echo "<td>" . $rowval['name'] . "</td>";
echo "<td>" . $rowval['salary'] . "</td>";
echo "</tr>";
}
echo "</table>";
mysqli_close($con);
?>
Output
![mysqli-query-function-in-php.jpg]()
PHP mysqli_real_connect() Function
The PHP MySQLi "mysqli_real_connect" function opens a connection to a MySQL server and this function returns true on success or false on failure.
Syntax
| mysqli_real_connect(connection,host,username,password,dbname,port,socket,flag); |
Parameters of the mysqli_real_connect function
The parameters of the function are:
| Parameter |
Description |
| connection |
It specifies the MySQL connection to use. |
| host |
It specifies a host name or IP address. |
| username |
It specifies the MySQL user name. |
| password |
It specifies the MySQL password. |
| dbname |
It specifies the default database to be used. |
| port |
It specifies the port number to attempt to connect to the MySQL server. |
| socket |
It specifies the socket to be used. |
| flag |
It specifies various connection options. |
Example
An example of the function is:
<?php
$con=mysqli_init();
if(!$con)
{
die("Failed");
}
if(mysqli_real_connect($con,"localhost","root","","mysql"))
{
echo "Connection has been established successfully.";
}
else
{
echo "Error: ".mysqli_error($con);
}
mysqli_close($con);
?>
Output
![mysqli-real-connect-function-in-php.jpg]()