1OracleݿָķЩ5
	ʵָ
	ʻָ

2ɾݵ﷨ʲô5
	DELETE FROM  WHERE ;

3дĸã6
	Ϊ˶ԱеļһַɢĴ洢ṹ
	ã߲ѯЧʺͼǿеΨһԡ
	ࣺΨһBλͼں
	
4дͼŵ㣿5
	ͼһԶƵķʽʾһ߶
	ŵ㣺
		ṩһּıȫ
		صݵĸ
		򻯵ûSQL
		ṹĸı
		ͨУһǶṩ
	
5ģѯЩ 5
	like where  like ֵͨ
	ͨ%ⳤַ_һַ
	between..and: where  between Сֵ and ֵ
	in: where  in (ֵ1,ֵ)
	
6д޸ĵ﷨ 5
	update  set 1=ֵ1,2=ֵ2 [where ]
	
7дSQLĴЩ4
	DQL ݲѯԣselect 
	DML ݲԣ insert update  delete 
	DDL ݶԣcreate table drop table ɾ
	DCL ݿԣ grant,revoke

8ۺϺЩ  5
	SUM()
	AVG()ƽ
	MAX()ֵ
	MIN()Сֵ
	COUNT(*)
	
9MySQLݿдʱҪЩ 5
	ͣǿԼĬֵԶ.
	
10дOracleݿرա׶ 5
	
		ʵ
		װݿ
		ݿ 
	ر
		رݿ
		жݿ
		رʵ
		
11MySQLûе%localhostĺ  
	%
	localhost
	
12mysqlĬϵĶ˿ںǶ٣  Ĭûʲô
	˿Ϊ3306
	Ĭûroot
	
13ݿⳣıЩ
	text
	char
	varchar
	
14Oracleзŵ								
	ƱĲѯ
	׹
	ڱݺͻָ
	ݰȫ
	
15Mysqlעͳ
	עͣ--#
	עͣ/*   */

16OracleȨɫЩԵʲô
	connectݿ
	resourceԽ洢̣ȣıɾɾĲݣܽͼû
	dbaԱдϵͳȨ
	
17OracleгĬûصʲô
	sysݿֵͼ洢 SYS ģʽСSYSûҪάϵͳϢ͹ʵ
	systemSYSTEM ĬϵϵͳԱûӵOracleʹõڲͼͨͨSYSTEMûݿûȨ޺ʹ洢
	scottSCOTTûOracle ݿһʾʻݿⰲװʱĬǽֹ
	
18OracleʹõĹʲô
	RMAN
	
19ʹ select ɲѯʱҪʾҪʹʲôؼ֣
	order by DESC
	
20ʹӡӡӽݲѯʱʲôݻᱻʵ
	ѯжԱУͬлᱻʾ
	ѯ
		᣺ȡȫԼص֣ұûƥļ¼ұֶʾΪ NULL
		᣺ȡұȫԼص֣ûƥļ¼ֶʾΪ NULL