动态执行存储过程条件处理-mysql教程-PHP中文网

动态执行存储过程条件处理

php中文网

发布： 2016-06-07 17:47:38

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动态执行条件处理

create procedure test(@where1 nvarchar(2000)) as declare @sql nvarchar(2000) set @sql= 'select * from tabletest where 1=1 '+ @where1 exec (@sql) exec test 'and where1 = @where1 ' exec test 'and where1 = @where1 and where2 = @where2 '

create procedure test(@where1 int, @where2 int, @where3 int)
as
if @where1 is not null and @where2 is null and @where3 is null
      select * from tabletest where where1 = @where1
if @where1 is not null and @where2 is not null and   @where3 is null
      select * from tabletest where where1 = @where1 and where2 = @where2
if @where1 is not null and @where2 is not null and @where3 is not null
      select * from tabletest where where1 = @where1 and where2 = @where2 and where3 = @where3

select *
from tabletest
where (where1 = @where1 or @where1 is null)
and (where2 = @where2 or @where2 is null)
and (where3 = @where3 or @where3 is null);

select *
from tabletest
where     where1 = case when @where1 is not null then @where1 else where1 end and
      where2 = case when @where2 is not null then @where2 else where2 end and
      where3 = case when @where3 is not null then @where3 else where3 end

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