db_add_column

Versions
4.7 – 6: db_add_column(&$ret, $table, $column, $type, $attributes = array())

Add a column to a database using syntax appropriate for PostgreSQL. Save result of SQL commands in $ret array.

Note: when you add a column with NOT NULL and you are not sure if there are already rows in the table, you MUST also add DEFAULT. Otherwise PostgreSQL won't work when the table is not empty, and db_add_column() will fail. To have an empty string as the default, you must use: 'default' => "''" in the $attributes array. If NOT NULL and DEFAULT are set the PostgreSQL version will set values of the added column in old rows to the DEFAULT value.

Parameters

$ret Array to which results will be added.

$table Name of the table, without {}

$column Name of the column

$type Type of column

$attributes Additional optional attributes. Recognized attributes: not null => TRUE|FALSE default => NULL|FALSE|value (the value must be enclosed in '' marks)

Return value

nothing, but modifies $ret parameter.

▸ 3 functions call db_add_column()

▾ 3 functions call db_add_column()

system_update_6005 in modules/system/system.install: Add language to url_alias table and modify indexes.
system_update_6011 in modules/system/system.install: Add language support to nodes
system_update_6016 in modules/system/system.install: Make {node}'s primary key be nid, change nid,vid to a unique key. Add primary keys to block, filters, flood, permission, and term_relation.

Code

./update.php, line 50

<?php
function db_add_column(&$ret, $table, $column, $type, $attributes = array()) {
  if (array_key_exists('not null', $attributes) and $attributes['not null']) {
    $not_null = 'NOT NULL';
  }
  if (array_key_exists('default', $attributes)) {
    if (is_null($attributes['default'])) {
      $default_val = 'NULL';
      $default = 'default NULL';
    }
    elseif ($attributes['default'] === FALSE) {
      $default = '';
    }
    else {
      $default_val = "$attributes[default]";
      $default = "default $attributes[default]";
    }
  }

  $ret[] = update_sql("ALTER TABLE {". $table ."} ADD $column $type");
  if (!empty($default)) {
    $ret[] = update_sql("ALTER TABLE {". $table ."} ALTER $column SET $default");
  }
  if (!empty($not_null)) {
    if (!empty($default)) {
      $ret[] = update_sql("UPDATE {". $table ."} SET $column = $default_val");
    }
    $ret[] = update_sql("ALTER TABLE {". $table ."} ALTER $column SET NOT NULL");
  }
}
?>

Use db_add_field() instead

Dave Reid - Thu, 2009-10-22 18:31

Don't use this function directly because this will only work on PostgreSQL. Use db_add_field() instead.