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                    1. JSON在線解析

                      1、創建數據庫
                      CREATE DATABASE database-name
                      
                      2、刪除數據庫
                      drop database dbname
                      
                      3、備份sql server
                      --- 創建 備份數據的 device
                      USE master
                      EXEC sp_addumpdevice 'disk', 'testBack', 'c:\mssql7backup\MyNwind_1.dat'
                      --- 開始 備份
                      BACKUP DATABASE pubs TO testBack
                      
                      4、創建新表
                      create table tabname(col1 type1 [not null] [primary key],col2 type2 [not null],..)
                      
                      根據已有的表創建新表:
                      A:create table tab_new like tab_old (使用舊表創建新表)
                      B:create table tab_new as select col1,col2… from tab_old definition only
                      
                      5、刪除新表
                      drop table tabname
                      
                      6、增加一個列
                      Alter table tabname add column col type
                      注:列增加后將不能刪除。DB2中列加上后數據類型也不能改變,唯一能改變的是增加varchar類型的長度。
                      
                      7、添加主鍵: Alter table tabname add primary key(col)
                      刪除主鍵: Alter table tabname drop primary key(col)
                      
                      8、創建索引:create [unique] index idxname on tabname(col….)
                      刪除索引:drop index idxname
                      注:索引是不可更改的,想更改必須刪除重新建。
                      
                      9、創建視圖:create view viewname as select statement
                      刪除視圖:drop view viewname
                      
                      10、幾個簡單的基本的sql語句
                      選擇:select * from table1 where 范圍
                      插入:insert into table1(field1,field2) values(value1,value2)
                      刪除:delete from table1 where 范圍
                      更新:update table1 set field1=value1 where 范圍
                      查找:select * from table1 where field1 like ’%value1%’ ---like的語法很精妙,查資料!
                      排序:select * from table1 order by field1,field2 [desc]
                      總數:select count as totalcount from table1
                      求和:select sum(field1) as sumvalue from table1
                      平均:select avg(field1) as avgvalue from table1
                      最大:select max(field1) as maxvalue from table1
                      最小:select min(field1) as minvalue from table1
                      

                      工具導航地圖

                      甘肃11选五基本走势图