OracleÖеÄdecodeÓ÷¨
OracleÖеÄdecodeÓ÷¨
Decode(Ìõ¼þ£¬Öµ1£¬ÏÔʾֵ1£¬Öµ2£¬ÏÔʾֵ2£¬…… Öµn£¬ÏÔʾֵn)
Ó¦ÓþÙÀý£º
select t.res_id,
t.res_size || '(kb)' as res_size,
decode(t.res_type,1,'Ä£°åÇø','0','ÎĵµÇø') res_type,
t.res_address,
t.createtime,
t.createuser
from t_cms_d_resource t
Ïà¹ØÎĵµ£º
oracleÁ¬½ÓÊý¾Ý¿â²âÊÔ´úÂë
/**
*
* ˵Ã÷£º
* £¨1£©±¾ÀýʹÓÃJDBC_ODBCÇŽøÐÐÊý¾Ý¿âÁ¬½Ó£¬¹Ê´ËÐèÒªODBCÊý¾ÝÔ´
* £¨2£©±¾ÀýÖÐSQLΪ¸üÐÂÓï¾ä£¬¹Ê´ËʹÓÃÔØÌåµÄexecuteUpdate·½·¨£¬²¢ÇÒ·µ»ØÊÜÓ°Ïì¼Ç¼Êý
* (3) ÅäÖÃÁ¬½ÓORACLEµÄodbcÊý¾ÝÔ´ora
*/ ......
²é¿´OracleÖ´Ðмƻ®µÄ¼¸ÖÖ·½·¨
Ò»¡¢Í¨¹ýPL/SQL Dev¹¤¾ß
1¡¢Ö±½ÓFile->New->Explain Plan Window£¬ÔÚ´°¿ÚÖÐÖ´ÐÐsql¿ÉÒԲ鿴¼Æ»®½á¹û¡£ÆäÖУ¬Cost±íʾcpuµÄÏûºÄ£¬µ¥Î»Îªn%£¬Cardinality±íʾִÐеÄÐÐÊý£¬µÈ¼ÛRows¡£
2¡¢ÏÈÖ´ÐÐ EXPLAIN PLAN FOR select * from tab ......
http://www.cuijie.net.cn/?cat=6
¸ü¸ÄÊý¾Ý¿âµÄ¹éµµÄ£Ê½ÐèÒªÖØÐÂÆô¶¯Êý¾Ý¿â£¬ÔÚmountģʽÏÂÐ޸쬼òÒª²½Öè
1 ÒÔshutdown immediate ·½Ê½¹Ø±ÕÊý¾Ý¿â
2 Æô¶¯ÊµÀýµ½mount״̬
3 ¸ü¸ÄÔËÐÐģʽ²¢´ò¿ªÊý¾Ý¿â
²Ù×÷²½Ö裺
1 µÇ¼Êý¾Ý¿â²é¿´Êý¾Ý¿âµÄ¹éµµ×´Ì¬
S ......
1.µ¼ÈëÊý¾ÝÃüÁimp userid=fkprod/fkprod full=y file=xxx.dmp
2.µ¼³öÊý¾Ý¿â¶ÔÏóÃüÁ
ʹÓÃtools--->export user objectÖ»Äܵ¼³öÊý¾Ý±í½Å±¾²»ÄÜ´ø³öÊý¾Ý,
»òÕßʹÓÃexp user/pwd file=/dir/xxx.dmp log=xxx.log full=y commit=y ignore=y
×¢Ò⣺Èç¹ûÄãÒªÔ¶³ÌµÇ¼µ½Êý¾Ý¿â·þÎñÆ÷µ¼³ö£¬¿ÉÒÔÔÚ±¾µØSQLPLUS×öÈçÏÂÃüÁ ......
ÖÚËùÖÜÖªµÄ¼¸¸ö½á¹û¼¯¼¯ºÏ²Ù×÷ÃüÁ½ñÌìÏêϸµØ²âÊÔÁËһϣ¬·¢ÏÖһЩÎÊÌ⣬¼Ç¼±¸¿¼¡£
¡¡¡¡¼ÙÉèÎÒÃÇÓÐÒ»¸ö±íStudent£¬°üÀ¨ÒÔÏÂ×Ö¶ÎÓëÊý¾Ý£º
¡¡¡¡drop table student;
¡¡¡¡create table student
¡¡¡¡(
¡¡¡¡id int primary key,
¡¡¡¡name nvarchar2(50) not null,
¡¡¡¡score number not null
¡¡¡¡);
¡¡¡¡insert into ......