AlterQuery  check_query_comment_column (children 2)
 ExpressionList (children 3)
  AlterCommand COMMENT_COLUMN (children 2)
   Identifier first_column
   Literal \'comment 1_2\'
  AlterCommand COMMENT_COLUMN (children 2)
   Identifier second_column
   Literal \'comment 2_2\'
  AlterCommand COMMENT_COLUMN (children 2)
   Identifier third_column
   Literal \'comment 3_2\'
 Identifier check_query_comment_column