/**
* Returns the SQL for the primary key of a Table object
* @return string
*/
public function getPrimaryKeyDDL(Table $table)
{
if ($table->hasPrimaryKey()) {
$keys = $table->getPrimaryKey();
//MySQL throws an 'Incorrect table definition; there can be only one auto column and it must be defined as a key'
//if the primary key consists of multiple columns and if the first is not the autoIncrement one. So
//this push the autoIncrement column to the first position if its not already.
$autoIncrement = $table->getAutoIncrementPrimaryKey();
if ($autoIncrement && $keys[0] != $autoIncrement) {
$idx = array_search($autoIncrement, $keys);
if ($idx !== false) {
unset($keys[$idx]);
array_unshift($keys, $autoIncrement);
}
}
return 'PRIMARY KEY (' . $this->getColumnListDDL($keys) . ')';
}
}
