PHP mysqli_autocommit() Function

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Definition and Usage

MySQL database have a feature named auto-commit if you turn it on, the the changes done in the databases are saved automatically and, If you turn it off, you need to save the changes explicitly. The mysqli_autocommit() is used turn on/off the auto-commit feature.

This function accepts a boolean value as a parameter. If you pass true to this function the auto-commit feature will be turned on and if you pass false this turns the auto-commit feature off.

Syntax

mysqli_autocommit($con, $mode);

Parameters

Return Values

The PHP mysqli_autocommit() function returns a boolean value which is true on success and false on failure.

PHP Version

This function was first introduced in PHP Version 5 and works works in all the later versions.

Example

Assume we have created a table named my_team in the database mydb, as follows −

CREATE TABLE my_team(
   ID INT PRIMARY KEY AUTO_INCREMENT,
   First_Name VARCHAR(255), 
   Last_Name VARCHAR(255), 
   Place_Of_Birth VARCHAR(255), 
   Country VARCHAR(255)
);

Following example demonstrates the usage of the mysqli_autocommit() function (in procedural style) −

<?php
   //Creating a connection
   $con = mysqli_connect("localhost", "root", "password", "mydb");

   //Setting auto commit to false
   mysqli_autocommit($con, False);

   //Inserting a records into the my_team table
   mysqli_query($con, "insert into my_team values(1, 'Shikhar', 'Dhawan', 'Delhi', 'India')");
   mysqli_query($con, "insert into my_team values(2, 'Jonathan', 'Trott', 'CapeTown', 'SouthAfrica')");
   mysqli_query($con, "insert into my_team values(3, 'Kumara', 'Sangakkara', 'Matale', 'Srilanka')");
   mysqli_query($con, "insert into my_team values(4, 'Virat', 'Kohli', 'Delhi', 'India')");

   //Verifying the contents of the table
   $result = mysqli_query($con, "SELECT * FROM my_team");
   print_r($result);

   //Closing the connection
   mysqli_close($con);
?>

This will produce following result −

mysqli_result Object
(
    [current_field] => 0
    [field_count] => 5
    [lengths] =>
    [num_rows] => 4
    [type] => 0
)

Since we have turned the auto-commit option off in the previous example, The records add will not be saved in the database and, if you verify the contents of the table in MySQL, it will be empty as shown below $minus;

mysql> select * from my_team;
Empty set (0.00 sec)

To save the changes in the database you need to commit the changes at the end of the program using the mysqli_commit() function as

mysqli_commit($con);

If you and verify the contents of the table my_team then, you can see the inserted records as shown below −

mysql> select * from my_team;
+----+------------+------------+----------------+-------------+
| ID | First_Name | Last_Name  | Place_Of_Birth | Country     |
+----+------------+------------+----------------+-------------+
|  1 | Shikhar    | Dhawan     | Delhi          | India       |
|  2 | Jonathan   | Trott      | CapeTown       | SouthAfrica |
|  3 | Kumara     | Sangakkara | Matale         | Srilanka    |
|  4 | Virat      | Kohli      | Delhi          | India       |
+----+------------+------------+----------------+-------------+
4 rows in set (0.00 sec)

Example

The syntax of this method in object oriented style is $con->autocommit(). Following is an example of this function in object oriented mode $minus;

//Creating a connection
$con = new mysqli("localhost", "root", "password", "mydb");

//Setting auto commit to true
$con->autocommit(FALSE);

//Inserting a records into the my_team table
$con->query( "insert into my_team values(1, 'Shikhar', 'Dhawan', 'Delhi', 'India')");
$con->query( "insert into my_team values(2, 'Jonathan', 'Trott', 'CapeTown', 'SouthAfrica')");
$con->query( "insert into my_team values(3, 'Kumara', 'Sangakkara', 'Matale', 'Srilanka')");
$con->query( "insert into my_team values(4, 'Virat', 'Kohli', 'Delhi', 'India')");

//Verifying the contents of the table
$result = $con->query( "SELECT * FROM my_team");
print_r($result);

//Saving the results
$con->commit();

//Closing the connection
$con -> close();
?>

This will produce following result −

mysqli_result Object
(
    [current_field] => 0
    [field_count] => 5
    [lengths] =>
    [num_rows] => 4
    [type] => 0
)

Example

The mysqli_autocommit() function also works as commit() on invoking, it saves the results of waiting queries to the database −

//Creating a connection
$con = mysqli_connect("localhost", "root", "password", "mydb");

//creating a table
mysqli_query($con, "Create table players (First_Name VARCHAR(255), Last_Name VARCHAR(255), Country VARCHAR(255))");

//Setting auto commit to false
mysqli_autocommit($con, False);

//Inserting a records into the my_team table
mysqli_query($con, "insert into players values('Shikhar', 'Dhawan', 'India')");
mysqli_query($con, "insert into players values('Jonathan', 'Trott', 'SouthAfrica')");

mysqli_autocommit($con, TRUE);

//Closing the connection
mysqli_close($con);
?>

After executing the program if you verify the contents of the players table you can observe the added records, as shown below −

mysql> select * from players;
+------------+-----------+-------------+
| First_Name | Last_Name | Country     |
+------------+-----------+-------------+
| Shikhar    | Dhawan    | India       |
| Jonathan   | Trott     | SouthAfrica |
+------------+-----------+-------------+
2 rows in set (0.00 sec)

Example

<?php
   $connection = mysqli_connect("localhost", "root", "password", "mydb");
   
   if (mysqli_connect_errno($connection)){
      echo "Failed to connect to MySQL: " . mysqli_connect_error();
   }
   
   mysqli_autocommit($connection,FALSE);   
   
   mysqli_query($connection, "create table test(Name VARCHAR(255), Age INT)");   
   
   mysqli_query($connection, "INSERT INTO test VALUES ('Sharukh', 25)");
   mysqli_query($connection, "INSERT INTO test VALUES ('Kalyan', 30)");
   
   mysqli_commit($connection);
   mysqli_close($connection);
?>

After executing the above program if you verify, the contents of the table test, you can see the inserted records as −

mysql> select * from test;
+---------+------+
| Name    | Age  |
+---------+------+
| Sharukh |   25 |
| Kalyan  |   30 |
+---------+------+
2 rows in set (0.00 sec)