mysqli query() Method
The mysqli::query() / mysqli_query() function is used to perform a query on the database.
For non-DML queries (not INSERT, UPDATE or DELETE), this function is similar to calling mysqli_real_query() followed by either mysqli_use_result() or mysqli_store_result().
Note: When passing a statement longer than max_allowed_packet of the server, this function returns different error codes depending on whether MySQL Native Driver (mysqlnd) or MySQL Client Library (libmysqlclient) is being used. The behavior is as follows:
- mysqlnd on Linux returns an error code of 1153. The error message means got a packet bigger than max_allowed_packet bytes.
- mysqlnd on Windows returns an error code 2006. This error message means server has gone away.
- libmysqlclient on all platforms returns an error code 2006. This error message means server has gone away.
Syntax
//Object-oriented style public mysqli::query(query, result_mode) //Procedural style mysqli_query(mysql, query, result_mode)
Parameters
mysql |
Required. For procedural style only: Specify a mysqli object returned by mysqli_connect() or mysqli_init(). |
query |
Required. Specify the SQL query string. |
result_mode |
Optional. Specify the result mode. It indicates how the result will be returned from the MySQL server. It can be one of the following:
|
Return Value
Returns false on failure. For successful queries which produce a result set, such as SELECT, SHOW, DESCRIBE or EXPLAIN, this function will return a mysqli_result object. For other successful queries, this function will return true.
Example: Object-oriented style
The example below shows the usage of mysqli::query() method.
<?php //establishing connection to the database $mysqli = new mysqli("localhost", "user", "password", "database"); if ($mysqli->connect_errno) { echo "Failed to connect to MySQL: ". $mysqli->connect_error; exit(); } //getting query result from the database $sql = "SELECT EmpID, Name, Age FROM Employee ORDER BY Age"; $result = $mysqli->query($sql); //closing the connection $mysqli->close(); //getting the number of rows in the result set $row_cnt = $result->num_rows; printf("Result set has %d rows.\n", $row_cnt); ?>
The output of the above code will be similar to:
Result set has 58 rows.
Example: Procedural style
The example below shows the usage of mysqli_query() function.
<?php //establishing connection to the database $mysqli = mysqli_connect("localhost", "user", "password", "database"); if (mysqli_connect_errno()) { echo "Failed to connect to MySQL: ". mysqli_connect_error(); exit(); } //getting query result from the database $sql = "SELECT EmpID, Name, Age FROM Employee ORDER BY Age"; $result = mysqli_query($mysqli, $sql); //closing the connection mysqli_close($mysqli); //getting the number of rows in the result set $row_cnt = mysqli_num_rows($result); printf("Result set has %d rows.\n", $row_cnt); ?>
The output of the above code will be similar to:
Result set has 58 rows.
❮ MySQLi Functions Reference