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--sqlplus
sqlplus;
sys /password as sysdba;
--²éÕÒÓû§ID£¨user#£©,Êý¾Ý¿âÀïÃæ´æ·ÅµÄÓû§¶¼ÊÇ´óд!
select user#,name,password from user$ where name ='FACT';
USER# NAME PASSWORD
91 FACT 7A0F2B316C212D67
-¸ù¾ÝÓû§ID ¸üÐÂÓû§Ãû¡£
update user$ set name= FACT where user#=91;
--Ìá½»¡£
commit;
--È·ÈÏÓû§ÃûÊÇ·ñ¸üгɹ¦¡£
select user#,name,password from user$ where USER# = 91;
USER# NAME PASSWORD
91 FACT 7A0F2B316C212D673
--ÐÞ¸ÄÓû§ÃÜÂë¡£
alter user fact identified by fact;
--ÊÖ¹¤Ö´Ðмì²éµã²Ù×÷£¬½«Database Buffer CacheÖеÄÊý¾ÝÇ¿ÖÆÐ´³öµ½Íâ´æ¡£
alter system checkpoint;
--Ç¿ÖÆË¢ÐÂShared Pool£¡ÒòΪOracleµÄÊý¾Ý×ÖµäÐÅÏ¢ÊÇ»º´æÔÚShared PoolµÄDictionary CacheÖеġ£
alter system flush shared_pool;
--È·ÈÏÃÜÂëÊÇ·ñÐ޸ijɹ¦¡£
select user#,name,password from user$ where USER# = 91;
USER# NAME PASSWORD
91 FACT 7A0F2B316C212D67
--²âÊÔÓû§ÊÇ·ñ¿ÉÓá£
conn fact/fact
Connected.
show user
USER is "FACT"
--ÖØÆôORACLE·þÎñ
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select 'true' from dual where (1,2) not in ((2,3),(2,null));
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¹Ø¼ü×Ö: oracle cast() º¯ÊýÎÊÌâ
SQL> create table t1(a varchar(10));
Table created.
SQL> insert into t1 values ('12.3456');
1 row created.
SQL> select round(a) from t1;
ROUND(A)
----------
12
SQL> select round(a,3) from t1;
ROUN ......
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