AlterQuery  mt_compact (children 2)
 ExpressionList (children 1)
  AlterCommand ADD_COLUMN (children 2)
   ColumnDeclaration n.y (children 2)
    DataType Array (children 1)
     ExpressionList (children 1)
      DataType String
    Literal Array_[\'qwqw\']
   Identifier n.x
 Identifier mt_compact
