Insert data into multiple tables using one form

To insert data into multiple tables using one form in PHP, you can use a single SQL statement with multiple INSERT INTO clauses, or you can use multiple individual SQL statements, one for each table.

Here is an example of using a single SQL statement with multiple INSERT INTO clauses:

<?php

$sql = "INSERT INTO table1 (column1, column2) VALUES ('$value1', '$value2');
        INSERT INTO table2 (column1, column2) VALUES ('$value3', '$value4');
        INSERT INTO table3 (column1, column2) VALUES ('$value5', '$value6')";

if ($conn->multi_query($sql) === true) {
  echo "New records created successfully";
} else {
  echo "Error: " . $sql . "<br>" . $conn->error;
}

Watch a course Learn object oriented PHP

Here is an example of using multiple individual SQL statements:

<?php

$sql1 = "INSERT INTO table1 (column1, column2) VALUES ('$value1', '$value2')";
$sql2 = "INSERT INTO table2 (column1, column2) VALUES ('$value3', '$value4')";
$sql3 = "INSERT INTO table3 (column1, column2) VALUES ('$value5', '$value6')";

if ($conn->query($sql1) === true && $conn->query($sql2) === true && $conn->query($sql3) === true) {
  echo "New records created successfully";
} else {
  echo "Error: " . $sql1 . "<br>" . $conn->error;
  echo "Error: " . $sql2 . "<br>" . $conn->error;
  echo "Error: " . $sql3 . "<br>" . $conn->error;
}

You should be careful with SQL injection when using these type of statements, you should use prepared statements to avoid it.