mysql - How to run multiple insert query in SQL using PHP in one go?

Question

I want to run mysql queries to insert data from a custom html form. Here I have to insert multiple set of data, some data to one table and some to other. Currently I am using the simple approach to send data to php page using jquery ajax and run multiple mysqli_query() functions one after another. But I guess when there will be large number of users, there will be problems related to speed. So can anyone suggest me a better way to do the same.

There are 5 tables in the database and each table has 7 to 10 columns that need to get different set of data, every time.

I want to run each query only if the previous insert query is successfully completed. That's why I am checking for the result every time and then running the next query, which makes me feel the issue of speed on large user base.

Answer 1

The problem is, I need to insert data to first table and if its successfully inserted then only run query for the second table.

This means you need a transaction.

A transaction is a set of queries that either all execute ok or if one fails - they all fail. This is to ensure you don't end up with crap data in your tables.

Do not

• Do not use multiquery.
• Do not use mysql_* function(s).
• Do not use bulk inserts.

People telling you to do that just have absolutely no clue what they're doing, ignore them.

Do

• Use PDO
• Use prepared statements
• Prepare the statement(s) ONCE, use them MULTIPLE times

Sample code - do NOT copy paste

$dsn = 'mysql:dbname=testdb;host=127.0.0.1;charset=utf8mb4';
$user = 'dbuser';
$password = 'dbpass';

$pdo = new PDO($dsn, $user, $password);
$pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

$insert['first'] = $pdo->prepare("INSERT INTO table SET col1 = :val, col2 = :val2");
$insert['second'] = $pdo->prepare("INSERT INTO another_table SET col1 = :val, col2 = :val2"); 

$pdo->beginTransaction();

$insert['first']->bindValue(':val', 'your value');
$insert['first']->bindValue(':val2', 'anothervalue');
$insert['first']->execute();

$insert['second']->bindValue(':val', 'your value');
$insert['second']->bindValue(':val2', 'anothervalue');
$insert['second']->execute();

$pdo->commit();

The code above will save the data in two tables ONLY if both inserts are successful.