SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 1)
    Function trimLeft (alias explain) (children 1)
     ExpressionList (children 1)
      Identifier explain
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Subquery (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 2)
          ExpressionList (children 1)
           Asterisk
          TablesInSelectQuery (children 1)
           TablesInSelectQueryElement (children 1)
            TableExpression (children 1)
             Function viewExplain (children 1)
              ExpressionList (children 3)
               Literal \'EXPLAIN\'
               Literal \'indexes = 1\'
               Subquery (children 1)
                SelectWithUnionQuery (children 1)
                 ExpressionList (children 1)
                  SelectQuery (children 5)
                   ExpressionList (children 2)
                    Identifier id
                    Identifier v1
                   TablesInSelectQuery (children 1)
                    TablesInSelectQueryElement (children 1)
                     TableExpression (children 1)
                      TableIdentifier tab
                   ExpressionList (children 1)
                    OrderByElement (children 1)
                     Identifier v1
                   Literal UInt64_10
                   Set
   Function like (children 1)
    ExpressionList (children 2)
     Identifier explain
     Literal \'%TopK%\'
