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MSSqlServer伪序列_MySQL
先创建一个序列表 if exists (select 1 from sysindexeswhere id = object_id('TSysSequence')and name = 'In_SeName'and indid > 0and indid < 255)drop index TSysSequence.In_SeNamegoif exists (select 1from sysobjectswhere id = object_id('TSysSequence')and type = 'U')drop table TSysSequencego /*======================================*//* Table: TSysSequence *//*=======================================*/ create table TSysSequence (SeName nvarchar(50) not null, Increment int not null default 1,CurVal bigint not null default 0)goif exists (select 1 from sys.extended_propertieswhere major_id = object_id('TSysSequence') and minor_id = 0)begindeclare @CurrentUser sysnameselect @CurrentUser = user_name()execute sp_dropextendedproperty 'MS_Description','user', @CurrentUser, 'table', 'TSysSequence'endselect @CurrentUser = user_name()execute sp_addextendedproperty 'MS_Description','
模拟oracle序列
不允许用户维护,数据库初始化以后不允许任何人修改其中的值。
默认生成名称为“DID”和“SID”的两个序列,意义为“数据序列号”和“系统序列号”。',
'user', @CurrentUser, 'table', 'TSysSequence'goinsert into TSysSequence (SeName,Increment,CurVal) values ('DID',1,0) ;insert into TSysSequence (SeName,Increment,CurVal) values ('SID',1,0) ; /*=======================================*//* Index: In_SeName *//*=======================================*/ create unique index In_SeName on TSysSequence (SeName ASC) go
再创建一个存储过程完成序列的使用
if exists (select 1from sysobjectswhere id = object_id('PGetSequenceValue')and type in ('P','PC'))drop procedure PGetSequenceValuegocreate procedure PGetSequenceValue@SeName nvarchar(50),@SeVal bigint outasbeginif not exists(select 1 from TSysSequence where SeName = @SeName) beginraiserror('不存在序列%s',16,1,@SeName)returnend update TSysSequence set @SeVal = CurVal + Increment, CurVal = CurVal + Increment where SeName = @SeNameendgo
使用方法
declare @ID1 intEXEC PGetSequenceValue 'SID',@ID1 OUTPUT select @ID1 declare @ID2 intEXEC PGetSequenceValue 'DID',@ID2 OUTPUT select @ID2
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