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select a.constraint_name, a.table_name, b.constraint_name
from user_constraints a, user_constraints b
where a.constraint_type = 'R'
and b.constraint_type = 'P'
and a.r_constraint_name = b.constraint_name
P ´ú±íÖ÷¼ü
R ´ú±íÍâ¼ü
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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 ......
Ò»¡¢ Hibernate½éÉÜ
HibernateÊÇ»ùÓÚ¶ÔÏó/¹ØϵӳÉ䣨ORM£¬Object/Relational Mapping£©µÄÒ»¸ö½â¾ö·½°¸¡£ORM·½°¸µÄ˼ÏëÊǽ«¶ÔÏóÄ£ÐͱíʾµÄ¶ÔÏóÓ³Éäµ½¹ØϵÐÍÊý¾Ý¿âÖУ¬»òÕß·´Ö®¡£HibernateÄ¿Ç°ÊÇORM˼ÏëÔÚJavaÖÐ×î³É¹¦¡¢×îÇ¿´óµÄʵÏÖ¡£ËüÓÚ2001ÄêµÄÄêÄ©·¢²¼µÚÒ»¸ö°æ±¾£¬Á¢¼´ÒýÆðÁ˹㷺µÄ×¢Òâ¡£2003Äê6Ô£ ......
insert into
select * into t_dest from t_src; -- ÒªÇóÄ¿±ê±í²»´æÔÚ
insert into t_dest(a, b) select a, b from t_src; -- ÒªÇóÄ¿±ê±íÒÑ´æÔÚ
¶¯Ì¬SQL
execute immediate ......
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1.ASCII
·µ»ØÓëÖ¸¶¨µÄ×Ö·û¶ÔÓ¦µÄÊ®½øÖÆÊý;
SQL> select ascii(A) A,ascii(a) a,ascii(0) zero,ascii( ) space from dual;
A A ZERO SPACE
--------- --------- --------- ---------
65 97 48 32
2.CHR
¸ø³öÕûÊý,·µ»Ø¶ÔÓ¦µÄ×Ö·û;
SQL> select chr(54740) zhao,chr(65) chr65 from dual;
......
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 ......