framework/db/QueryBuilder.php
public function dropForeignKey($name, $table)
    {
        return 'ALTER TABLE ' . $this->db->quoteTableName($table)
            . ' DROP CONSTRAINT ' . $this->db->quoteColumnName($name);
    }
public function dropForeignKey($name, $table)
    {
        return 'ALTER TABLE ' . $this->db->quoteTableName($table)
            . ' DROP CONSTRAINT ' . $this->db->quoteColumnName($name);
    }
Builds a SQL statement for dropping a foreign key constraint.
@param string $name the name of the foreign key constraint to be dropped. The name will be properly quoted by the method.
@param string $table the table whose foreign is to be dropped. The name will be properly quoted by the method.
@return string the SQL statement for dropping a foreign key constraint.