在sql中比較兩個相同的表數據Date

Question

如何編寫SQL語句來比較昨天的當前日期和日期。表格具有相同的列。我需要檢查選擇的兩個日期列中哪些數據不同，並顯示兩個表之間的變化。

這裏是存儲過程，我開始

CREATE PROCEDURE [dbo].[usp_CompareNetworksandRatings] 
     @media_month_id smallint, 
     @rating_category_id tinyint, 
     @rate_date datetime 
    AS 
    BEGIN 
    SET NOCOUNT ON; 

    SELECT DISTINCT 
     nn.nielsen_network_id, 
     nn.code, 
     nn.name 
    FROM 
     daily_ratings dr (NOLOCK) 
    JOIN media_months mm (NOLOCK) ON mm.id=dr.media_month_id 
     AND mm.id=@media_month_id 
    JOIN uvw_nielsen_network_universes nn (NOLOCK) ON nn.nielsen_network_id=dr.nielsen_network_id 
     AND nn.start_date<=mm.start_date AND (nn.end_date>=mm.start_date OR nn.end_date IS NULL) 
    WHERE 
     dr.rating_category_id=@rating_category_id 
     AND dr.media_month_id=@media_month_id 
     AND dr.rating_date=@rate_date 
    ORDER BY 
     nn.code 

Answer 1

您需要的情況下構建要檢查每一列。類似這樣的：

select case when t2.f1 <> t1.f1 then 'yes' else 'no' end f1_changed