如果第一条语句有结果,则执行,否则执行第二条语句,该怎么解决

如果第一条语句有结果,则执行,否则执行第二条语句
如果第一条语句有结果,则执行,
如果第一条语句执行结果为空,则执行第二条语句
怎么写

SQL code

SELECT TOP 1 *FROM (  SELECT *  FROM TEST   WHERE 日期 BETWEEN '2012-7-16'AND'2012-7-18') AS AORDER BY 数量 DESCSELECT TOP 1 *FROM TEST ORDER BY 日期 DESC

[解决办法]
改为if @@rowcount=0
[解决办法]
delete from table1
select * from Table1
IF @@Rowcount = 0
select 123
[解决办法]

SQL code

 SELECT TOP 1         * FROM    ( SELECT    *           FROM      TEST           WHERE     日期 BETWEEN '2012-7-16' AND '2012-7-18'         ) AS A ORDER BY 数量 DESC IF @@ROWCOUNT = 0      BEGIN         SELECT TOP 1                 *         FROM    TEST         ORDER BY 日期 DESC     END
[解决办法]
如果第一条语句有结果,则执行  

就是两个select 都要呢 还是执行第一个 第二个不执行？
如果是继续执行那么参考2、3楼
如果是第二个不执行
SQL code
if exists(SELECT 1 FROM TEST  WHERE 日期 BETWEEN '2012-7-16'AND'2012-7-18')SELECT TOP 1 *FROM (  SELECT *  FROM TEST   WHERE 日期 BETWEEN '2012-7-16'AND'2012-7-18') AS AORDER BY 数量 DESCelseSELECT TOP 1 *FROM TEST ORDER BY 日期 DESC
[解决办法]
SQL code
if exists(SELECT TOP 1 *FROM (  SELECT *  FROM TEST   WHERE 日期 BETWEEN '2012-7-16'AND'2012-7-18') AS AORDER BY 数量 DESC)SELECT TOP 1 *FROM (  SELECT *  FROM TEST   WHERE 日期 BETWEEN '2012-7-16'AND'2012-7-18') AS AORDER BY 数量 DESCelseSELECT TOP 1 *FROM TEST ORDER BY 日期 DESC 

 

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