SelectWithUnionQuery (children 2)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 3)
    Identifier table
    Identifier name
    Identifier comment
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier system.columns
   Function and (children 1)
    ExpressionList (children 2)
     Function equals (children 1)
      ExpressionList (children 2)
       Identifier table
       Literal \'check_query_comment_column\'
     Function equals (children 1)
      ExpressionList (children 2)
       Identifier database
       Function currentDatabase (children 1)
        ExpressionList
 Identifier PrettyCompactNoEscapes