1 field.api.php hook_field_schema_alter(&$schema, $field)

Allow modules to alter the schema for a field.

@since 1.26.4 Hook added.

Parameters

array $schema: The schema definition as returned by hook_field_schema().

array $field: The field definition.

See also

field_retrieve_schema()

Related topics

Field Types API Define field types. Hooks Allow modules to interact with the Backdrop core.

File

core/modules/field/field.api.php, line 277
Hooks provided by the Field module.

Code

function hook_field_schema_alter(&$schema, $field) {
  if ($field['type'] == 'image') {
    // Alter the length of a field.
    $schema['columns']['alt']['length'] = 2048;
    // Add an additional column of data.
    $schema['columns']['additional_column'] = array(
      'description' => "Additional column added to image field table.",
      'type' => 'varchar',
      'length' => 128,
      'not null' => FALSE,
    );
    // Add an additional index.
    $schema['indexes']['fid_additional_column'] = array('fid', 'additional_column');
  }
}