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select 2|8       --10
select 2|8|1    --11
select 10&8    --8,°üº¬,10=8+2
select 10&2    --2,°üº¬,10=2+8
select 10&4    --0,²»°üº¬
select 19&16  --16,°üº¬,19=16+2+1
select 19&8    --0,°üº¬,19=16+2+1
select * from SqlBitOperation where FBitTags&4=4
 
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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,'³Ô·¹',1)
INSERT [RightTags] ([Pkid],[RightsName],[RightsTag]) VALUES ( 2,'À­Êº',2)
INSERT [RightTags] ([Pkid],[RightsName],[RightsTag]) VALUES ( 3,'´òÅÚ',4)
INSERT [RightTags] ([Pkid],[RightsName],[RightsTag]) VALUES ( 4,'ÅÝæ¤',8)
INSERT [RightTags] ([Pkid],[RightsName],[RightsTag]) VALUES ( 5,'Éú×Ó',16)
INSERT [RightTags] ([Pkid],[RightsName],[RightsTag]) VALUES ( 6,'°ü¶þÄÌ',32)
SET IDENTITY_INSERT [RightTags] OFF

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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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binary 8000
bit 1
char 8000
datetime 8
decimal 17
float 8
image 16
int 4
money 8
nchar 8000
ntext 16
numeric 17
nvarchar 8000
real 4
smalldatetime 4
smallint 2
smallmoney 4
sql_variant 8016
sysname 256
text 16
tim ......

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SELECT * from users WHERE name = 'a' OR 't'='t';
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