Inserting a row to a table with auto_increment column

Question

I'm working on a table that has 4 columns and the first one is an auto incrementing integer called id.

If I'm going to insert into this table using mysqli prepared statements I keep having trouble inserting a query that works. Using phpMyAdmin It tells me to give it NULL. I've tried this:

$query = "INSERT INTO tbl (id, col2, col3, col4) VALUES ('NULL', ?, ?, ?)";
$stmt -> bind_param("ssi", $col2, $col3, $col4)

And this

$query = "INSERT INTO tbl (id, col2, col3, col4) VALUES (NULL, ?, ?, ?)";
$stmt -> bind_param("ssi", $col2, $col3, $col4)

And only give bind_param 3 arguments (the last 3). Neither of those work. I also tried this:

$null = NULL;
$query = "INSERT INTO tbl (id, col2, col3, col4) VALUES (?, ?, ?, ?)";
$stmt -> bind_param("issi", $null, $col2, $col3, $col4);

None of these work. Is there a standardized way of inserting into this type of table?

Answer 1

Just skip the id field, MySQL will fill it automatically:

$query = "INSERT INTO tbl (col2, col3, col4) VALUES (?, ?, ?)";
$stmt->bind_param("ssi", $col2, $col3, $col4)

Answer 2

If the id field is the auto_increment, then just don't specify it in your insert query :

$query = "INSERT INTO tbl (col2, col3, col4) VALUES (?, ?, ?)";

And, of course, don't try to bind any parameter to it ;-)

As it's generated by MySQL, there is no need to pass that column.