Explain EXPLAIN SYNTAX (children 1)
 SelectWithUnionQuery (children 1)
  ExpressionList (children 1)
   SelectQuery (children 2)
    ExpressionList (children 1)
     Function plus (children 1)
      ExpressionList (children 2)
       Function sum (children 1)
        ExpressionList (children 1)
         Function minus (children 1)
          ExpressionList (children 2)
           Identifier decimal32
           Literal UInt64_2
       Function sum (children 1)
        ExpressionList (children 1)
         Function minus (children 1)
          ExpressionList (children 2)
           Identifier decimal32
           Literal UInt64_3
    TablesInSelectQuery (children 1)
     TablesInSelectQueryElement (children 1)
      TableExpression (children 1)
       TableIdentifier test_table
