SQL位运算
SQL位运算
select 2|8 --10
select 2|8|1 --11
select 10&8 --8,包含,10=8+2
select 10&2 --2,包含,10=2+8
select 10&4 --0,不包含
select 19&16 --16,包含,19=16+2+1
select 19&8 --0,包含,19=16+2+1
select * from SqlBitOperation where FBitTags&4=4
在权限中的应用
1、两张表
（1）、操作与权限标志表
if exists (select * from sysobjects where id = OBJECT_ID('[RightTags]') and OBJECTPROPERTY(id, 'IsUserTable') = 1)
DROP TABLE [RightTags]
CREATE TABLE [RightTags] (
[Pkid] [int] IDENTITY (1, 1) NOT NULL,
[RightsName] [nvarchar] (50) NOT NULL,
[RightsTag] [int] NOT NULL DEFAULT (0))
ALTER TABLE [RightTags] WITH NOCHECK ADD CONSTRAINT [PK_RightTags] PRIMARY KEY NONCLUSTERED ( [Pkid] )
SET IDENTITY_INSERT [RightTags] ON
INSERT [RightTags] ([Pkid],[RightsName],[RightsTag]) VALUES ( 1,'吃饭',1)
INSERT [RightTags] ([Pkid],[RightsName],[RightsTag]) VALUES ( 2,'拉屎',2)
INSERT [RightTags] ([Pkid],[RightsName],[RightsTag]) VALUES ( 3,'打炮',4)
INSERT [RightTags] ([Pkid],[RightsName],[RightsTag]) VALUES ( 4,'泡妞',8)
INSERT [RightTags] ([Pkid],[RightsName],[RightsTag]) VALUES ( 5,'生子',16)
INSERT [RightTags] ([Pkid],[RightsName],[RightsTag]) VALUES ( 6,'包二奶',32)
SET IDENTITY_INSERT [RightTags] OFF
（2）、用户与权限表
if exists (select * from sysobjects where id = OBJECT_ID('[RightUsers]') and OBJECTPROPERTY(id, 'IsUserTable') = 1)
DROP TABLE [RightUsers]
CREATE TABLE [RightUsers] (
[Pkid] [int] IDENTITY (1, 1) NOT NULL,
[FUser] [nvarchar] (50) NOT NULL,
[UserRights] [int] NOT NULL DEFAULT (0))
ALTER TABLE [RightUsers] WITH NOCHECK ADD CONSTRAINT [PK_RightUsers] PRIMARY KEY NONCLUSTERED ( [Pkid] )
SET IDENTITY_INSERT [RightUsers] ON
INSERT [RightUsers] ([Pkid],[FUser],[UserRights]) VALUES ( 1
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==============================
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原网站无法访问，故保留google快照
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