Explain EXPLAIN QUERY TREE (children 1)
 SelectWithUnionQuery (children 1)
  ExpressionList (children 1)
   SelectQuery (children 2)
    ExpressionList (children 1)
     Function tuple (children 1)
      ExpressionList (children 2)
       Function sum (children 1)
        ExpressionList (children 1)
         Function if (children 1)
          ExpressionList (children 3)
           Function equals (children 1)
            ExpressionList (children 2)
             Function modulo (children 1)
              ExpressionList (children 2)
               Identifier number
               Literal UInt64_2
             Literal UInt64_0
           Function toNullable (children 1)
            ExpressionList (children 1)
             Literal UInt64_1
           Literal UInt64_0
       Literal NULL
    TablesInSelectQuery (children 1)
     TablesInSelectQueryElement (children 1)
      TableExpression (children 1)
       Function numbers (children 1)
        ExpressionList (children 1)
         Literal UInt64_10
