oracleÐÐתÁÐ
select i.sid,i.sname,i.birthday,i.schooltime,i.sphone,c.classname,a.assnname,sum(decode(subject,'ÓïÎÄ',s.score,0)) as chin,
sum(decode(subject,'Êýѧ',s.score,0)) as math,
sum(decode(subject,'Ó¢Óï',s.score,0)) as eng from student_info i
left join student_expand e on i.sid = e.sid left join student_class c on
c.classid = e.classid left join student_assn a on a.assnid = e.assnid left join student_score s on s.sid = i.sid
group by i.sid,i.sname,i.birthday,i.schooltime,i.sphone,c.classname,a.assnname;
ÐÐתÁÐ:
decode(subject,'Êýѧ',s.score,0) Ó÷¨:Èç¹ûsubject»áµÈÓÚÊýѧ ,Ôò×îºóÖµµÈÓÚ s.score ·ñÔòÖµµÈÓÚ: 0
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mkdir ~/.ssh
chmod 700 ~/.ssh
ssh-keygen -t rsa
ssh-keygen -t dsa
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ssh rdb1 cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys
ssh rdb1 cat ~/.ssh/id_dsa.pub >> ~/.ssh/authorized_keys
ssh rdb2 ......
1import java.sql.*;
2import java.util.logging.Level;
3import java.util.logging.Logger;
4
5/** *//**
6 * Title: JDBCÁ¬½ÓÊý¾Ý¿â
7 * Description: ±¾ÊµÀýÑÝʾÈçºÎʹÓÃJDBCÁ¬½ÓOracleÊý¾Ý¿â£¬²¢ÑÝʾÌí¼ÓÊý¾ÝºÍ²éѯÊý¾Ý.
8 */
9public class JDBCExampl ......
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1. ²é¿´Oracle´´½¨¹ýÄÄЩÓû§
>select username from all_users;
2. ²é¿´Oracle´´½¨¹ýÄÄЩ±í¿Õ¼ä£¬±í¿Õ¼äµÄÃû×ֺʹóС
>select t.tablespace_name, round(sum(bytes/(1024*1024)),0) ts_size
from dba_tablespaces t, dba_data_files d
wher ......
oracleÖÐʹÓÃon delete cascadeºÍon delete set nullÀ´½¨Á¢Íâ¼ü
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