Gets the whole database schema.
The returned schema will include any modifications made by any module that implements hook_schema_alter().
$rebuild: If true, the schema will be rebuilt instead of retrieved from the cache.
function drupal_get_complete_schema($rebuild = FALSE) {
static $schema = array();
if (empty($schema) || $rebuild) {
// Try to load the schema from cache.
if (!$rebuild && ($cached = cache_get('schema'))) {
$schema = $cached->data;
}
else {
$schema = array();
// Load the .install files to get hook_schema.
// On some databases this function may be called before bootstrap has
// been completed, so we force the functions we need to load just in case.
if (function_exists('module_load_all_includes')) {
// This function can be called very early in the bootstrap process, so
// we force the module_list() cache to be refreshed to ensure that it
// contains the complete list of modules before we go on to call
// module_load_all_includes().
module_list(TRUE);
module_load_all_includes('install');
}
require_once DRUPAL_ROOT . '/includes/common.inc';
// Invoke hook_schema for all modules.
foreach (module_implements('schema') as $module) {
// Cast the result of hook_schema() to an array, as a NULL return value
// would cause array_merge() to set the $schema variable to NULL as well.
// That would break modules which use $schema further down the line.
$current = (array) module_invoke($module, 'schema');
// Set 'module' and 'name' keys for each table, and remove descriptions,
// as they needlessly slow down cache_get() for every single request.
_drupal_schema_initialize($current, $module);
$schema = array_merge($schema, $current);
}
drupal_alter('schema', $schema);
// If the schema is empty, avoid saving it: some database engines require
// the schema to perform queries, and this could lead to infinite loops.
if (!empty($schema) && drupal_get_bootstrap_phase() == DRUPAL_BOOTSTRAP_FULL) {
cache_set('schema', $schema);
}
if ($rebuild) {
cache_clear_all('schema:', 'cache', TRUE);
}
}
}
return $schema;
}