OracleËæ»úº¯Êý—dbms_random
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DBMS_RANDOM°üµÄÏêϸÐÅÏ¢£º
select text from all_source
where name = 'DBMS_RANDOM'
and type = 'PACKAGE' order by line;
¡ô TYPE num_array
2.Ó¦ÓþÙÀý
SELECT DBMS_RANDOM.RANDOM from DUAL;
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select abs(mod(dbms_random.random,100)) from dual
3.½ø½×˵Ã÷
dbms_randomÓÖÓÐк¯ÊýÁË¿ÉÒÔʵÏÖÕâЩ¹¦ÄÜ
FUNCTION value RETURN NUMBER;
FUNCTION value (low IN NUMBER, high IN NUMBER) RETURN NUMBER;
FUNCTION normal RETURN NUMBER;
FUNCTION string (opt char, len NUMBER) RETURN VARCHAR2;
²úÉúNµ½MÖ®¼äµÄËæ»úÊý
SELECT DBMS_RANDOM.VALUE(N,M) from DUAL;
ȱʡDBMS_RANDOM.VALUE·µ»Ø0µ½1Ö®¼äµÄËæ»úÊý
SQL> select dbms_random.value, dbms_random.value(55,100) from dual;
VALUE DBMS_RANDOM.VALUE(55,100)
--------------- -----------------------------
0.714469037747011 68.5593418279622
&n
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select TRUNC(SYSDATE) from dual;
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SELECT TRUNC(SYSDATE)+1-1/86400 from dual;
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select to_char(sysdate,'D'),to_char(sysdate,'DAY') from dual;
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[oracle@liwei admin]$ sqlplus / as sysdba
SQL*Plus: Release 10.2.0.1.0 - Production on Thu May 1 15:55:18 2008
Copyright (c) 1982, 2005, Oracle. All rights reserved.
Connected to an idle instance.
SQL> quit
Disconnected
[oracle@liwei admin]$ sqlplus "/ as sysdba"
SQL*Plus: Release 10 ......
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