how to insert an empty value in mysql date type field?

Question

How to insert a NULL or empty value in a mysql date type field (NULL = yes).

If I try to insert an empty value it inserts 0000-00-00 but I want to keep it empty or NULL.

Thanks for help.

UPDATE

Please see that I have set default value as NULL

  `payment_due_on` date DEFAULT NULL,

Ok OKies

I have got it working now

function get_mysqlDate($date, $delimiter='/') {
    if(check_empty($date)) {
     return 'NULL';
    }
    list($d, $m, $y) = explode($delimiter, $date);
    //$datetime = strtotime($date);
    return "'".date('Y-m-d', mktime(0,0,0,$m, $d, $y))."'";
}




"... SET mydate = ".get_mysqldate($_POST['mydate'])." ...."

Cheers

Answer 1

If that's happening, it's because the column has been defined with NOT NULL or with a default '0000-00-00'. You need to change the column definition to allow NULLs and have no default.

Your insert should be specifying NULL, as well, not '', if that's what you mean by "empty value".

Answer 2

Just omit the field when your doing your insert.

Say your table is like this:

CREATE TABLE mytable(
`name` VARCHAR(30) NOT NULL,
`payment_due_on` date DEFAULT NULL);

If you want to insert something without the date, use:

INSERT INTO mytable (name) VALUES ('name here');

Answer 3

phew.. was struggling with this null thing a bit.

I had a php script that copies, formats and stores data from one database A to database B. there was a date field in database A with NULL values. but when I copied it it became 0000-00-00 in my database B.

finally figure out it was because I was putting single quotes around NULL like ('NULL').

$started_date = mysql_result($databaseA['result'],$i,"start_date");

    if (empty($published_at_date)){
     $insert_sql .= "NULL,  ";
    } 
    else 
    {
     $insert_sql .= " '" . mysql_real_escape_string($started_date) ."', ";
    }

This fixed it.