Wie übergeben Null-Wert an gespeicherte Prozedur in Sql

Question

Dies ist meine gespeicherte Prozedur, die Eingabe von Listbox und Anzeige von Datensätzen im Zusammenhang mit ausgewählten Element. aber wenn ich nichts aus Listbox auswähle, dann müssen alle Datensätze angezeigt werden, was nicht passiert ist.

Das ist mein Stored Procedure

USE [MyDb] 
GO 
/****** Object: StoredProcedure [dbo].[usp_SearchCAMAFunctionalObsolescence] Script Date: 10/18/2016 12:30:08 PM ******/ 
SET ANSI_NULLS ON 
GO 
SET QUOTED_IDENTIFIER ON 
GO 

ALTER PROCEDURE [dbo].[usp_SearchCAMAFunctionalObsolescence] 
@section as nvarchar(max), 
@quality as nvarchar(max), 
@style as nvarchar(max) 

As 
Begin 

set nocount on; 
Declare @Where as varchar(max) 
Declare @Select as varchar(max) 

Set @Select = ' Distinct vi.struct_no as structure,a.assesmt_no as assessment,a.parcel_no as parcel, o.own_last+'' , ''+o.own_first as taxpayer, id.year_built as built, id.effect_age as age, id.mkt_adj as fo, vi.aprais_val as mktvalue 
        From assessments a 
        inner join parcel p on a.parcel_no = p.parcel_no 
        inner join valueimp vi on vi.assesmt_no = a.assesmt_no 
        inner join owner o on o.id = a.owner_id 
        inner join imp_details id on id.improvementId = vi.id and (id.isdeleted is null or id.isdeleted = 0) 
        inner join quality_details qd on qd.quality_id = id.quality_id 
        inner join section_details sd on sd.section_id = id.section_id 
        inner join style_details stdl on stdl.style_id = id.style_id' 



Set @Where = ' where (' + @section + ' is null or sd.section_id = ' + @section + ') and (' + @quality + ' is null or qd.quality_id = ' + @quality + ') and (' + @style + ' is null or stdl.style_id = ' + @style + ')' 


DECLARE @QUERY NVARCHAR(MAX)  

SET @QUERY= 'Select '+ @SELECT + @WHERE 
print @QUERY 
EXEC sp_executesql @QUERY , N'@section as int ,@quality as int,@style as int' ,@section ,@quality,@style 

END 

if i execute stored procedure in this way 
// EXEC usp_SearchCAMAFunctionalObsolescence 'null','null','null' 
it display all records. 

but i need to execute stored procedure in this way 
// EXEC usp_SearchCAMAFunctionalObsolescence null,null,null 
and it not display anything 

Answer 1

Sie benötigen keine dynamische SQL für diesen Zweck. Verwenden Sie IFNULL in den WHERE Anweisungen, wenn Sie mysql verwenden. (Für SQL Server Verwendung ISNULL und für Oracle verwenden NVL statt.)

Wenn die Eingangsgröße null ist, dann wird das Skript die aktuelle Spalte Wert zurück.

USE [MyDb] 
GO 
/****** Object: StoredProcedure [dbo].[usp_SearchCAMAFunctionalObsolescence] Script Date: 10/18/2016 12:30:08 PM ******/ 
SET ANSI_NULLS ON 
GO 
SET QUOTED_IDENTIFIER ON 
GO 

ALTER PROCEDURE [dbo].[usp_SearchCAMAFunctionalObsolescence] 
@section as nvarchar(max), 
@quality as nvarchar(max), 
@style as nvarchar(max) 

As 
Begin 

set nocount on; 

SELECT Distinct vi.struct_no as structure,a.assesmt_no as assessment,a.parcel_no as parcel, o.own_last+'' , ''+o.own_first as taxpayer, id.year_built as built, id.effect_age as age, id.mkt_adj as fo, vi.aprais_val as mktvalue 
        From assessments a 
        inner join parcel p on a.parcel_no = p.parcel_no 
        inner join valueimp vi on vi.assesmt_no = a.assesmt_no 
        inner join owner o on o.id = a.owner_id 
        inner join imp_details id on id.improvementId = vi.id and (id.isdeleted is null or id.isdeleted = 0) 
        inner join quality_details qd on qd.quality_id = id.quality_id 
        inner join section_details sd on sd.section_id = id.section_id 
        inner join style_details stdl on stdl.style_id = id.style_id 
WHERE sd.section_id =IFNULL(@section,sd.section_id) 
    AND qd.quality_id = IFNULL(@quality,qd.quality_id) 
    AND stdl.style_id = IFNULL(@style,stdl.style_id) 

END 

Answer 2

Warum nicht eine gespeicherte Proc erstellen, die ungefilterte Ergebnisse liefert und dann, dass in Ihrem Code aufrufen, wenn keine Auswahl getroffen wird?

CREATE PROCEDURE [dbo].[usp_SearchCAMAFunctionalObsolescenceUnfiltered] 
As 
Begin 

set nocount on; 

SELEcT Distinct vi.struct_no as structure,a.assesmt_no as assessment,a.parcel_no as parcel, o.own_last+'' , ''+o.own_first as taxpayer, id.year_built as built, id.effect_age as age, id.mkt_adj as fo, vi.aprais_val as mktvalue 
From assessments a 
inner join parcel p on a.parcel_no = p.parcel_no 
inner join valueimp vi on vi.assesmt_no = a.assesmt_no 
inner join owner o on o.id = a.owner_id 
inner join imp_details id on id.improvementId = vi.id and (id.isdeleted is null or id.isdeleted = 0) 
inner join quality_details qd on qd.quality_id = id.quality_id 
inner join section_details sd on sd.section_id = id.section_id 
inner join style_details stdl on stdl.style_id = id.style_id 

END