isnull(left( CASE (lower(LEFT(site_name, CASE (charindex("_", site_name, 0) - 1) WHEN "-1" THEN "0" ELSE charindex("_", site_name, 0) - 1 END))) WHEN "yongan" THEN "永安" WHEN "datian" THEN "大田" WHEN "taining" THEN "泰宁" WHEN "shaxian" THEN "沙县" WHEN "sanming" THEN "三明" WHEN "jianning" THEN "建宁" WHEN "jiangle" THEN "将乐" WHEN "ninghua" THEN "宁化" WHEN "qingliu" THEN "清流" WHEN "youxi" THEN "尤溪" WHEN "mingxi" THEN "明溪" END,2),left(site_name,2)) as city 语法上正确吗?
动态sql语句基本语法 1 :普通SQL语句可以用Exec执行 eg: Select * from tableName Exec('select * from tableName') Exec sp_executesql N'select * from tableName' -- 请注意字符串前一定要加N 2:字段名,表名,数据库名之类作为变量时,必须用动态SQL eg: declare @fname varchar(20) set @fname = 'FiledName' Select @fname from tableName -- 错误,不会提示错误,但结果为固定值FiledName,并非所要。 Exec('select ' + @fname + ' from tableName') -- 请注意 加号前后的 单引号的边上加空格 当然将字符串改成变量的形式也可 declare @fname varchar(20) set @fname = 'FiledName' --设置字段名 declare @s varchar(1000) set @s = 'select ' + @fname + ' from tableName' Exec(@s) -- 成功 exec sp_executesql @s -- 此句会报错 declare @s Nvarchar(1000) -- 注意此处改为nvarchar(1000) set @s = 'select ' + @fname + ' from tableName' Exec(@s) -- 成功 exec sp_executesql @s -- 此句正确 3. 输出参数 declare @num int, @sqls nvarchar(4000) set @sqls='select count(*) from tableName' exec(@sqls) --如何将exec执行结果放入变量中? declare @num int, @sqls nvarchar(4000) set @sqls='select @a=count(*) from tableName ' exec sp_executesql @sqls,N'@a int output',@num output select @num
WHEN "-1" THEN "0" ELSE charindex("_", site_name, 0) - 1 END)))
WHEN "yongan" THEN "永安" WHEN "datian" THEN "大田" WHEN "taining" THEN "泰宁"
WHEN "shaxian" THEN "沙县" WHEN "sanming" THEN "三明" WHEN "jianning" THEN "建宁"
WHEN "jiangle" THEN "将乐" WHEN "ninghua" THEN "宁化" WHEN "qingliu" THEN "清流"
WHEN "youxi" THEN "尤溪" WHEN "mingxi" THEN "明溪" END,2),left(site_name,2)) as city
语法上正确吗?
1 :普通SQL语句可以用Exec执行 eg: Select * from tableName
Exec('select * from tableName')
Exec sp_executesql N'select * from tableName' -- 请注意字符串前一定要加N 2:字段名,表名,数据库名之类作为变量时,必须用动态SQL eg:
declare @fname varchar(20)
set @fname = 'FiledName'
Select @fname from tableName -- 错误,不会提示错误,但结果为固定值FiledName,并非所要。
Exec('select ' + @fname + ' from tableName') -- 请注意 加号前后的 单引号的边上加空格 当然将字符串改成变量的形式也可
declare @fname varchar(20)
set @fname = 'FiledName' --设置字段名 declare @s varchar(1000)
set @s = 'select ' + @fname + ' from tableName'
Exec(@s) -- 成功
exec sp_executesql @s -- 此句会报错 declare @s Nvarchar(1000) -- 注意此处改为nvarchar(1000)
set @s = 'select ' + @fname + ' from tableName'
Exec(@s) -- 成功
exec sp_executesql @s -- 此句正确 3. 输出参数
declare @num int,
@sqls nvarchar(4000)
set @sqls='select count(*) from tableName'
exec(@sqls)
--如何将exec执行结果放入变量中? declare @num int,
@sqls nvarchar(4000)
set @sqls='select @a=count(*) from tableName '
exec sp_executesql @sqls,N'@a int output',@num output
select @num