SelectWithUnionQuery (children 2)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 3)
    Identifier errors.name (alias labels)
    Identifier value
    Literal \'ch_errors_total\' (alias name)
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier system.errors
   Literal UInt64_1
 Identifier Null
