Same name in this branch
  1. 6.x includes/database.pgsql.inc \_db_create_field_sql()
  2. 6.x includes/database.mysql-common.inc \_db_create_field_sql()

Create an SQL string for a field to be used in table creation or alteration.

Before passing a field out of a schema definition into this function it has to be processed by _db_process_field().

Parameters

$name: Name of the field.

$spec: The field specification, as per the schema data structure format.

Related topics

Schema API
A Drupal schema definition is an array structure representing one or more tables and their related keys and indexes. A schema is defined by hook_schema(), which usually lives in a modulename.install file.
5 calls to _db_create_field_sql()
db_add_field in includes/database.mysql-common.inc
Add a new field to a table.
db_add_field in includes/database.pgsql.inc
Add a new field to a table.
db_change_field in includes/database.mysql-common.inc
Change a field definition.
db_create_table_sql in includes/database.mysql-common.inc
Generate SQL to create a new table from a Drupal schema definition.
db_create_table_sql in includes/database.pgsql.inc
Generate SQL to create a new table from a Drupal schema definition.

File

includes/database.mysql-common.inc, line 165
Functions shared between mysql and mysqli database engines.

Code

function _db_create_field_sql($name, $spec) {
  $sql = "`" . $name . "` " . $spec['mysql_type'];
  if (in_array($spec['type'], array(
    'varchar',
    'char',
    'text',
  )) && isset($spec['length'])) {
    $sql .= '(' . $spec['length'] . ')';
  }
  elseif (isset($spec['precision']) && isset($spec['scale'])) {
    $sql .= '(' . $spec['precision'] . ', ' . $spec['scale'] . ')';
  }
  if (!empty($spec['unsigned'])) {
    $sql .= ' unsigned';
  }
  if (!empty($spec['not null'])) {
    $sql .= ' NOT NULL';
  }
  if (!empty($spec['auto_increment'])) {
    $sql .= ' auto_increment';
  }
  if (isset($spec['default'])) {
    if (is_string($spec['default'])) {
      $spec['default'] = "'" . $spec['default'] . "'";
    }
    $sql .= ' DEFAULT ' . $spec['default'];
  }
  if (empty($spec['not null']) && !isset($spec['default'])) {
    $sql .= ' DEFAULT NULL';
  }
  return $sql;
}