Is Empty/Is Nonempty

In the expanded constraint editor](fa_advanced-limit-editor.html) there is support for expressions is Empty/is nonempty (Empty/Filled).

Пусто corresponds to the function funcIsNull of SQLWhereLanguageDef.

Непусто corresponds to the function of funcNotIsNull ExternalLangDef.

The possibility expression is Empty/is nonempty

Expression is Empty/is nonempty can be applied to:

  • own properties,
  • properties of datalow,
  • masters,
  • properties of the masters (the expression of the Пусто(A. B. C) interpreted as A==null || A. B==null || A. B. C==null).

Incomparable with null properties and Empty/is nonempty

If you have a class with a property Кредит СуммаКредита real type, the translation in [LINQProvider LinqProvider) it will be presented as follows:
var ds = (SQLDataService)DataServiceProvider.DataService;
IQueryable<Кредит> limit = ds.Query<Кредит>(Кредит.Views.C__КредитE).Where(x => (x.СуммаКредита as object) == null);

and transfer in lcs:

Function lf = FunctionBuilder.BuildIsNull<Кредит>(x => x.СуммаКредита);