laminas-db: $AlterTable->dropConstraint() Throw error on MySQL,There is no support for "DROP CONSTRAINT"

I’m dropping a constraint on mysql5.6, code:

$AlterTable = new Ddl\AlterTable($test_table_name);
$AlterTable->dropConstraint('text_UniqueKey');

echo $sql->buildSqlString($AlterTable,$adapter);

$adapter->query(
    $sql->buildSqlString($AlterTable,$adapter),
    $adapter::QUERY_MODE_EXECUTE
);

And this code output :

ALTER TABLE `test` DROP CONSTRAINT `text_UniqueKey`

Here is the problem, Mysql nerver support the Syntax “DROP CONSTRAINT”, so it throw an error :

SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'CONSTRAINT `text_UniqueKey`' at line 2

Note: $adapter config array is

'db' => array(
    'driver' => 'Pdo_Mysql',
    'hostname' => 'localhost',
    'username' => 'root',
    'password' => 'abc123',
    'database' => 'easypay',
)

Help ! What to do now ???

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Originally posted by @solody at https://github.com/zendframework/zend-db/issues/36