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HomeDatabaseMysql TutorialSQL数据库开发中的一些经典代码

1.按姓氏笔画排序: Select * From TableName Order By CustomerName Collate Chinese_PRC_Stroke_ci_as 2.数据库加密: select encrypt('原始密码') select pwdencrypt('原始密码') select pwdcompare('原始密码','加密后密码') = 1--相同;否则不相同 encrypt

   1.按姓氏笔画排序:

  Select * From TableName Order By CustomerName Collate Chinese_PRC_Stroke_ci_as

  2.数据库加密:

  select encrypt('原始密码')

  select pwdencrypt('原始密码')

  select pwdcompare('原始密码','加密后密码') = 1--相同;否则不相同 encrypt('原始密码')

  select pwdencrypt('原始密码')

  select pwdcompare('原始密码','加密后密码') = 1--相同;否则不相同

  3.取回表中字段:

  declare @list varchar(1000),@sql nvarchar(1000)

  select @list=@list+','+b.name from sysobjects a,syscolumns b where a.id=b.id and a.name='表A'

  set @sql='select '+right(@list,len(@list)-1)+' from 表A'

  exec (@sql)

  4.查看硬盘分区:

  EXEC master..xp_fixeddrives

  5.比较A,B表是否相等:

  if (select checksum_agg(binary_checksum(*)) from A)

  =

  (select checksum_agg(binary_checksum(*)) from B)

  print '相等'

  else

  print '不相等'

  6.杀掉所有的事件探察器进程:

  DECLARE hcforeach CURSOR GLOBAL FOR SELECT 'kill '+RTRIM(spid) FROM master.dbo.sysprocesses

  WHERE program_name IN('SQL profiler',N'SQL 事件探查器')

  EXEC sp_msforeach_worker '?'

  7.记录搜索:

  开头到N条记录

  Select Top N * From 表

  -------------------------------

  N到M条记录(要有主索引ID)

  Select Top M-N * From 表 Where ID in (Select Top M ID From 表) Order by ID Desc

  ----------------------------------

  N到结尾记录

  Select Top N * From 表 Order by ID Desc

  8.如何修改数据库的名称:

  sp_renamedb 'old_name', 'new_name'

  9:获取当前数据库中的所有用户表

  select Name from sysobjects where xtype='u' and status>=0

  10:获取某一个表的所有字段

  select name from syscolumns where id=object_id('表名')

  11:查看与某一个表相关的视图、存储过程、函数

  select a.* from sysobjects a, syscomments b where a.id = b.id and b.text like '%表名%'

  12:查看当前数据库中所有存储过程

  select name as 存储过程名称 from sysobjects where xtype='P'

  13:查询用户创建的所有数据库

  select * from master..sysdatabases D where sid not in(select sid from master..syslogins where)

  或者

  select dbid, name AS DB_NAME from master..sysdatabases where sid 0x01

  14:查询某一个表的字段和数据类型

  select column_name,data_type from information_schema.columns

  where table_name = '表名'

  [n].[标题]:

  Select * From TableName Order By CustomerName

  [n].[标题]:

  Select * From TableName Order By CustomerName

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