[support] Drupal 7 Schema API / datetime => char?

[Tim Gustafson]

So, in the Drupal 6 version of a lot of my modules, I made prodigious use of the datetime column type.  Now, Drupal 7 says those pesky data-specific column types are off-limits.  I created a hook_update_N function to convert datetime columns into char columns that looks like this:

function hook_update_N() {
  db_change_field(
    "foo",
    "column_1",
    "column_1",
    array(
      "type" => "char",
      "length" => 20,
      "not null" => true,
      "default" => "0000-00-00 00:00:00",
    )
  );

  db_change_field(
    "foo",
    "column_2",
    "column_2",
    array(
      "type" => "char",
      "length" => 20,
      "not null" => true,
      "default" => "0000-00-00 00:00:00",
    )
  );
}

And when I run update.php, I now get:

Failed: PDOException: SQLSTATE[42000]: Syntax error or access violation: 1067 Invalid default value for 'column_2': ALTER TABLE {foo} CHANGE `created_on` `column_1` CHAR(20) NOT NULL DEFAULT '0000-00-00 00:00:00'; Array ( ) in db_change_field() (line 2984 of includes/database/database.inc).

Please not that it's complaining about the default value on column_2 when it's trying to update column_1.

How does one convert a table with two or more datetime columns to char(20) columns in Drupal 7?

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Tim Gustafson                                                tjg at soe.ucsc.edu
Baskin School of Engineering                                     831-459-5354
UC Santa Cruz                                         Baskin Engineering 317B
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