Explain EXPLAIN (children 1)
 SelectWithUnionQuery (children 1)
  ExpressionList (children 1)
   SelectQuery (children 3)
    ExpressionList (children 1)
     Asterisk
    TablesInSelectQuery (children 1)
     TablesInSelectQueryElement (children 1)
      TableExpression (children 1)
       Function s3 (children 1)
        ExpressionList (children 2)
         Literal \'http://localhost:11111/test/a.tsv\'
         Literal \'TSV\'
    Function in (children 1)
     ExpressionList (children 2)
      Identifier c1
      Subquery (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 2)
          ExpressionList (children 1)
           Identifier c1
          TablesInSelectQuery (children 1)
           TablesInSelectQueryElement (children 1)
            TableExpression (children 1)
             Function s3 (children 1)
              ExpressionList (children 2)
               Literal \'http://localhost:11111/test/a.tsv\'
               Literal \'TSV\'
