定义临时变量,同时直接在Convert中用CASE WHEN 切换查询条件. 代码为: DECLARE @REFFLAG VARCHAR SET @REFFLAG = (select (case when decl_submit_time is null then 'Y' else 'N' end) IS_NULL_SUBMIT_TIME from T_BC_DEC_DECLARATION where dec_id=@p_dec_id) SELECT ... FROM T_BC_DEC_GOODS t...
T-SQL CASE WHEN 使用小例 用一个SQL语句完成以下查询,从book表中查询出price,当price在10到20之间(包含10和20)时返回“10 to 20”,当price为空返回“Unknown”,其他情况返回原price的值 selectcasewhenCONVERT(int, price)>=10andCONVERT(int, price)<=20then'10 to 20'whenpriceisnullthen'Unknown'elsepr...
TSQL中的case when使用小例 用一个SQL语句完成以下查询,从book表中查询出price,当price在10到20之间(包含10和20)时返回“10 to 20”,当price为空返回“Unknown”,其他情况返回原price的值 selectcasewhenCONVERT(int,price)>=10andCONVERT(int,price)<=20then'10 to 20'whenpriceisnullthen'Unknown'elseprice...
T-SQL是SQL Server的查询语言,是一种用于与数据库进行交互的编程语言。CASE子句是T-SQL中的一种流程控制语句,用于根据不同条件执行不同的操作。WHEN NULL是CASE子句中的一个条件,用于检查特定列是否为NULL。 在实际应用中,CASE子句和WHEN NULL可以用于各种场景,例如数据清洗、数据转换和数据聚合等。例如,在数据清洗...
TSQL是一种用于管理和操作关系型数据库的编程语言,它支持使用CASE语句来更新多个列,但更新操作的结果取决于特定的值。 CASE语句是一种条件表达式,它允许根据不同的条件执行不同的操作。在TSQL...
select t1.user_time, round( (count(distinct case when datediff(t2.user_time,t1.user_time) = 1 then t2.uid end) /count(distinct t1.uid) ) ,2) as uv_left_rate from ( -- 新用户数据: select t.uid,date_format(t.in_time,'%Y-%m-%d') as user_time from ( select *,row_number...
In working with our customers, I come across some very interesting patterns in T-SQL. Not all of these patterns are complex on the face of it, but their impact can sometimes be substantial. Here is a simple example to demonstrate what I am referring to: SELECT CASE WHEN EXISTS (SELECT ...
参考答案: SELECT custid , region FROM Sales.Customers ORDER BY CASE WHEN region IS NULL THEN 1 ELSE 0 END , region; 参考资料: 《SQL2008技术内幕:T-SQL语言基础》文章标签: 云解析DNS SQL 索引 数据库 关键词: SQL查询 SQL单表查询 SQL sql查询 SQL T-SQL SQL基础 悟空...
In SQL Server 2014 (12.x), FOREIGN KEY constraints are not supported with memory-optimized tables. Feature clustered index Specify a nonclustered index. In the case of a primary key index be sure to specify PRIMARY KEY NONCLUSTERED. Feature DDL inside transactions Memory-optimized tables and ...
"SELECT INTO" with indexes? "Simple" SQL to check for alpha or numeric charcters isn't working right "String or binary data would be truncated.\r\nThe statement has been terminated." "String or binary data would be truncated" and field specifications “Unable to enlist in the ...