Preparing a MySQL INSERT/UPDATE statement with DEFAULT values

The only "workaround" I know for this is to use Coalesce() and Default(fieldname)

E.g.

$pdo = new PDO("mysql:host=localhost;dbname=test", 'localonly', 'localonly'); $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);$pdo->exec("  CREATE TEMPORARY TABLE foo (    id int auto_increment,    x int NOT NULL DEFAULT 99,    y DATETIME NOT NULL DEFAULT '2010-03-17 01:00:00',    z varchar(64) NOT NULL DEFAULT 'abc',    primary key(id)  )");$stmt = $pdo->prepare('  INSERT INTO    foo    (x,y,z)  VALUES    (      Coalesce(:x, Default(x)),      Coalesce(:y, Default(y)),      Coalesce(:z, Default(z))    )');$stmt->bindParam(':x', $x);$stmt->bindParam(':y', $y);$stmt->bindParam(':z', $z);$testdata = array(  array(null, null, null),  array(1, null, 'lalala'),  array(null, '2009-12-24 18:00:00', null));foreach($testdata as $row) {  list($x,$y,$z) = $row;  $stmt->execute();}unset($stmt);foreach( $pdo->query('SELECT id,x,y,z FROM foo', PDO::FETCH_NUM) as $row) {  echo join(', ', $row), "\n";}

prints

1, 99, 2010-03-17 01:00:00, abc2, 1, 2010-03-17 01:00:00, lalala3, 99, 2009-12-24 18:00:00, abc

I tried replying to VolkerK answer, but couldnt find how. :( I'm kinda new to all this.

Anyway, I created a mysql function to use in conjuction with his COALESCE idea

CREATE FUNCTION NULLDEFAULT(colname VARCHAR(64), tablename VARCHAR(64), dbname VARCHAR(64)) RETURNS longtext DETERMINISTIC READS SQL DATABEGIN    DECLARE retval longtext;    SELECT        COLUMN_DEFAULT INTO retval     FROM        information_schema.COLUMNS    WHERE        TABLE_NAME = tablename    AND        COLUMN_NAME = colname    AND        TABLE_SCHEMA = dbname;    RETURN retval;END

You would use it like this:

$stmt = $pdo->prepare("  INSERT INTO    foo    (x,y,z)  VALUES    (      Coalesce(:x, NULLDEFAULT('x', 'foo', 'database')),      Coalesce(:y, NULLDEFAULT('y', 'foo', 'database')),      Coalesce(:z, NULLDEFAULT('z', 'foo', 'database'))    )");

That will return null if the column has no default value, and won't trigger the "Column has no default value" Error.

Of course you could modify it to not require the database parameter

Try changing this:

$statement = $pdoObject->    prepare("INSERT INTO table1 (column1,column2) values (?,?)");$statement->execute(array('value1','DEFAULT'));

To this:

$statement = $pdoObject->    prepare("INSERT INTO table1 (column1,column2) values (?,DEFAULT)");$statement->execute(array('value1'));

It seems to me that your original code will give you this:

INSERT INTO table1 (column1,column2) values ('value1','DEFAULT')

My code should give you this:

INSERT INTO table1 (column1,column2) values ('value1',DEFAULT)