For situations looking up a code and description i want an exact code match to show in preference to a full text search.

Accordingly this is a first attempt which shows full text search matches until there is an exact code match if it exists.
It needs a tidy but seems to work.

Code:
Procedure SuggestionsFindFullText String sSearch tSuggestion[] ByRef aSuggestions
        Boolean bContinue bCase  bOldRelate bNeedsRelate
        Integer iFile iColumn iDescriptionColumn iIndex iLen iRow iMax
        Handle hoServer
        String sDescription sValue sValueToSearch sLowSearch
        Get Server to hoServer
        Get Data_File  to iFile
        Get Data_Field to iColumn       
        If ((hoServer <> 0) and (iFile <> 0)) Begin
            Get piMaxResults to iMax
            Get pbCaseSensitive to bCase
            Get piFindIndex to iIndex
            If (iIndex <= 0) Begin
                Get_Attribute DF_FIELD_INDEX of iFile iColumn to iIndex
            End
            Get No_Relate_State of hoServer to bOldRelate
            Get DDOConstraintNeedsRelate of hoServer iIndex to bNeedsRelate
            Set No_Relate_State of hoServer to (not(bNeedsRelate))
            Move (Lowercase(sSearch)) to sLowSearch
            Move True to bContinue
            Move (Length(sSearch)) to iLen
            Move 0 to iRow
            Get piDescriptionField to iDescriptionColumn
            //  Find first record
            Send Request_Read of hoServer FIRST_RECORD iFile iIndex
            While (Found and (iRow < iMax))
                Get_Field_Value iFile iColumn to sValue
                Move (Trim(sValue)) to sValue
                If (iDescriptionColumn) Begin
                    Get_Field_Value iFile iDescriptionColumn to sDescription
                    Move (Append(svalue,Trim(sDescription))) to sValueToSearch
                End
                If ((not(bCase) and Lowercase(sValue) = sLowSearch) or (bCase and sValue = sSearch)) Begin
                    // Test exact match first
                    // Clear all full text values
                    Move (ResizeArray(aSuggestions,0)) to aSuggestions
                    Move 0 to iRow
                    Move (SerializeRowID(GetRowID(iFile))) to aSuggestions[iRow].sRowId
                    Move (Trim(sValue)) to aSuggestions[iRow].aValues[0]
                    Move (Trim(sDescription)) to aSuggestions[iRow].aValues[1]
                  Else Begin
                    // Else full text search
                    If ((bCase and sValueToSearch contains sSearch) or (not(bCase) and Lowercase(sValueToSearch) contains sLowSearch)) Begin
                        Move (SerializeRowID(GetRowID(iFile)))  to aSuggestions[iRow].sRowId
                        Move (Trim(sValue)) to aSuggestions[iRow].aValues[0]
                        If (sDescription) Begin
                            Move (Trim(sDescription)) to aSuggestions[iRow].aValues[1]
                        End
                        Increment iRow
                    End    
                End
                Send Request_Read of hoServer GT iFile iIndex
            Loop
            Set No_Relate_State of hoServer to bOldRelate
        End
    End_Procedure