如何从PHP插入NULL值？

Question

Let x is a column of the table t allowing NULL values.

Which value should $value variable take for the following PDO statement to insert NULL value?

$db->prepare("INSERT t SET x=:x")->execute(array(':x'=>$value));

Answer 1

You simply insert it as null :

$db->prepare("INSERT t SET x=:x")->execute(array(':x'=>null));

If you want, you can also add the data type of PDO::PARAM_NULL .