I can not make it work I have searched the forum and found some suggestions, but I have not got anything to work. I know that psSQLFilter is only applied to the (main) table find, is it impossible?

Code:
/////////////////// Works //////////////////// 
   Object oANVAND_DD is a Anvand_DataDictionary
    Procedure OnConstrain
        Constrain anvand.acgrupp eq 31910
    End_Procedure
    End_Object




    Object oANBREG_DD is a Anbreg_DataDictionary
        Set DDO_Server to oANVAND_DD


        Set pbUseDDSQLFilters to True


        Procedure OnConstrain
            Forward Send OnConstrain
        Constraind Anbreg.Kalkylar eq 2021
        End_Procedure


    End_Object




    Object oANVAND_DD is a Anvand_DataDictionary
    Procedure OnConstrain
        //Constrain anvand.acgrupp eq 31910
    End_Procedure
    End_Object


    Set Main_DD to oANBREG_DD
    Set Server to oANBREG_DD


/////////////////// Don't Work ////////////////////


It gives this error
General error. 42000 (102)--[Microsoft][ODBC Driver 13 for SQL Server][SQL Server]Incorrect syntax near '='.  Table = Anbreg (3)
Fel: 12289
Felkälla = MSSQLDRV.Find


    Object oANBREG_DD is a Anbreg_DataDictionary
        Set DDO_Server to oANVAND_DD


        Set pbUseDDSQLFilters to True


        Procedure OnConstrain
            Forward Send OnConstrain
        Move "SELECT [Anbreg].[SIGN] from [Anbreg] where (select [Anbreg].[SIGN] = [anvand].[SIGN] and  [anvand].[ACGRUPP] = '31910' )" to sFilter
        Set psSQLFilter to sFilter
        End_Procedure


    End_Object


    Set Main_DD to oANBREG_DD
    Set Server to oANBREG_DD