我的升级历程：

1. 第一次长级完发现问答数据丢失
2. 重新运行升级程序，文章数据也丢失
3. 回档到5.1
4. 数据库升级过程闪显红色错误，没在意跳过
5. 测试发布信息，出现“把数据保存到数据库附加表 `dede_addoninfos` 时出错……”
6. 本地安装完整dedecms5.3，对比表dede_addoninfos，索引键值等一切相同，这个表没问题，那就是数据有问题了
7. 回档到5.1，这次做一点备份一点，回档是个力气活，很枯燥
8. 重回第四步，本次开了QQ准备好了”Ctrl+Alt+A”，顺便截住数据库升级过程中的一次报错（约1秒后会消失，升级最终不会报错，所以每一次页面涮新都要盯好不能只看最后的升级成功页面提示）提示“insert dede_arctiny(……”
9. 查dede_arctiny表，发现没这个dede_arctin，大喜，从5.3默认库中导出SQL，回到新升级的库发现有dede_arctiny表（第一次看错库了，开了三个数据库界面5.3默认的、5.1老数据、刚升级后的数据，把5.1老的当成刚升级完的- -！），查表新库中的dede_arctiny，有数据但条数不对，那问题就出在某一条记录上，操作SQL最终排查到dede_addoninfos中aid=0这条记录无法被导入，强删，再导
10. 成功，余下就是二次开发和升级模板的事了

心得是什么，看上面的红色字块

说明：拷贝表(拷贝数据,源表名：a 目标表名：b)
SQL: insert into b(a, b, c) select d,e,f from b;

说明：显示文章、提交人和最后回复时间
SQL: select a.title,a.username,b.adddate from table a,(select max(adddate) adddate from table where table.title=a.title) b

说明：外连接查询(表名1：a 表名2：b)
SQL: select a.a, a.b, a.c, b.c, b.d, b.f from a LEFT OUT JOIN b ON a.a = b.c

说明：日程安排提前五分钟提醒
SQL: select * from 日程安排 where datediff(‘minute’,f开始时间,getdate())>5

说明：两张关联表，删除主表中已经在副表中没有的信息
SQL:
delete from info where not exists ( select * from infobz where info.infid=infobz.infid )

说明：–
SQL:
SELECT A.NUM, A.NAME, B.UPD_DATE, B.PREV_UPD_DATE FROM TABLE1,(SELECT X.NUM, X.UPD_DATE, Y.UPD_DATE PREV_UPD_DATE FROM (SELECT NUM, UPD_DATE, INBOUND_QTY, STOCK_ONHAND FROM TABLE2 WHERE TO_CHAR(UPD_DATE,’YYYY/MM’) = TO_CHAR(SYSDATE, ‘YYYY/MM’)) X, (SELECT NUM, UPD_DATE, STOCK_ONHAND FROM TABLE2 WHERE TO_CHAR(UPD_DATE,’YYYY/MM’) = TO_CHAR(TO_DATE(TO_CHAR(SYSDATE, ‘YYYY/MM’) ¦¦ ‘/01′,’YYYY/MM/DD’) – 1, ‘YYYY/MM’) ) Y, WHERE X.NUM = Y.NUM （+）AND X.INBOUND_QTY + NVL(Y.STOCK_ONHAND,0) <> X.STOCK_ONHAND ) B WHERE A.NUM = B.NUM

说明：–
SQL:
select * from studentinfo where not exists(select * from student where studentinfo.id=student.id) and 系名称=’”&strdepartmentname&”‘ and 专业名称=’”&strprofessionname&”‘ order by 性别,生源地,高考总成绩

说明：
从数据库中去一年的各单位电话费统计(电话费定额贺电化肥清单两个表来源）
SQL:
SELECT a.userper, a.tel, a.standfee, TO_CHAR(a.telfeedate, ‘yyyy’) AS telyear, SUM(decode(TO_CHAR(a.telfeedate, ‘mm’), ‘01′, a.factration)) AS JAN, SUM(decode(TO_CHAR(a.telfeedate, ‘mm’), ‘02′, a.factration)) AS FRI, SUM(decode(TO_CHAR(a.telfeedate, ‘mm’), ‘03′, a.factration)) AS MAR, SUM(decode(TO_CHAR(a.telfeedate, ‘mm’), ‘04′, a.factration)) AS APR, SUM(decode(TO_CHAR(a.telfeedate, ‘mm’), ‘05′, a.factration)) AS MAY, SUM(decode(TO_CHAR(a.telfeedate, ‘mm’), ‘06′, a.factration)) AS JUE,SUM(decode(TO_CHAR(a.telfeedate, ‘mm’), ‘07′, a.factration)) AS JUL, SUM(decode(TO_CHAR(a.telfeedate, ‘mm’), ‘08′, a.factration)) AS AGU, SUM(decode(TO_CHAR(a.telfeedate, ‘mm’), ‘09′, a.factration)) AS SEP, SUM(decode(TO_CHAR(a.telfeedate, ‘mm’), ‘10′, a.factration)) AS OCT, SUM(decode(TO_CHAR(a.telfeedate, ‘mm’), ‘11′, a.factration)) AS NOV,SUM(decode(TO_CHAR(a.telfeedate, ‘mm’), ‘12′, a.factration)) AS DEC FROM (SELECT a.userper, a.tel, a.standfee, b.telfeedate, b.factration FROM TELFEESTAND a, TELFEE b WHERE a.tel = b.telfax) a GROUP BY a.userper, a.tel, a.standfee, TO_CHAR(a.telfeedate, ‘yyyy’)

说明：四表联查问题：
SQL: select * from a left inner join b on a.a=b.b right inner join c on a.a=c.c inner join d on a.a=d.d where …..

说明：得到表中最小的未使用的ID号
SQL:
SELECT (CASE WHEN EXISTS(SELECT * FROM Handle b WHERE b.HandleID = 1) THEN MIN(HandleID) + 1 ELSE 1 END) as HandleID FROM Handle WHERE NOT HandleID IN (SELECT a.HandleID – 1 FROM Handle a)

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 name=’sa’)
或者
select dbid, name AS DB_NAME from master..sysdatabases where sid <> 0×01

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