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CREATE DATABASE database-name
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drop database dbname
3¡¢ËµÃ÷£º±¸·Ýsql server
--- ´´½¨ ±¸·ÝÊý¾ÝµÄ device
USE master
EXEC sp_addumpdevice 'disk', 'testBack', 'c:\mssql7backup\MyNwind_1.dat'
--- ¿ªÊ¼ ±¸·Ý
BACKUP DATABASE pubs TO testBack
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create table tabname(col1 type1 [not null] [primary key],col2 type2 [not null],..)
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A£ºcreate table tab_new like tab_old (ʹÓÃ¾É±í´´½¨Ð±í)
B£ºcreate table tab_new as select col1,col2… from tab_old definition only
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drop table tabname
6¡¢ËµÃ÷£ºÔö¼ÓÒ»¸öÁÐ
Alter table tabname add column col type
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7¡¢ËµÃ÷£ºÌí¼ÓÖ÷¼ü£º Alter table tabname add primary key(col)
˵Ã÷£ºÉ¾³ýÖ÷¼ü£º Alter table tabname drop primary key(col)
8¡¢ËµÃ÷£º´´½¨Ë÷Òý£ºcreate [unique] index idxname on tabname(col….)
ɾ³ýË÷Òý£ºdrop index idxname
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9¡¢ËµÃ÷£º´´½¨ÊÓͼ£ºcreate view viewname as select statement
ɾ³ýÊÓͼ£ºdrop view viewname
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Ñ¡Ôñ£ºselect * from table1 where ·¶Î§
²åÈ룺insert into table1(field1,field2) values(value1,value2)
ɾ³ý£ºdelete from table1 where ·¶Î§
¸üУºupdate table1 set field1=value1 where ·¶Î§
²éÕÒ£ºselect * from table1 where field1 like ’%value1%’ ---likeµÄÓï·¨ºÜ¾«Ã²é×ÊÁÏ!
ÅÅÐò£ºselect * from table1 order by field1,field2 [desc]
×ÜÊý£ºselect count as totalcount from table1
ÇóºÍ£ºselect sum(field1) as sumvalue from table1
ƽ¾ù£ºselect avg(field1) as avgvalue from table1
×î´ó£ºselect max(field1) as maxvalue from table1
×îС£ºselect min(field1) as minvalue from table1
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A£º UNION ÔËËã·û
UNION ÔËËã·ûͨ¹ý×éºÏÆäËûÁ½¸ö½á¹û±í£¨ÀýÈç TABLE1 ºÍ TABLE2£©²¢ÏûÈ¥±íÖÐÈκÎÖظ´ÐжøÅÉÉú³öÒ»¸ö½á¹û±í¡£µ± ALL Ëæ UNION Ò»ÆðʹÓÃʱ£¨¼´ UNION ALL£©£¬²»Ïû³ýÖظ´ÐС£Á½ÖÖÇé¿öÏ£¬ÅÉÉú±íµÄÿһÐв»ÊÇÀ´×Ô


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SELECT Sname
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SELECT Sno
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WHERE Grade>60;
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SQLʹÓÃС½á

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sql ֪ʶ

 select datediff(month,'2009-11-02','2009-12-01')
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declare @t table(a datetime,b datetime);
insert @t
select '2009-11-02','2009-12-01' UNION ......

SQLÓïÑÔ»ù´¡¿¼ºË(Ò»)(oracle)

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CREATE TABLE BOOK(
    NO CHAR(8) PRIMARY KEY,
    TITLE VARCHAR2(50) NOT NULL,
    AUTHOR VARCHAR2(20) ,
    PUBLISH VARCHAR2(20),
    PUB_DA ......

SQL SERVER Ò×»ìÏýµÄÊý¾ÝÀàÐÍ

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