OracleËæ»úº¯Êý—dbms_random
1.»ù´¡ÈÏʶ
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;
ÔÙ½øÒ»²½µÄÒªÇ󣬱ÈÈ磬²úÉúÒ»¸ö0£100µÄËæ»úÊý£¬ÉÔ΢±äͨһϾͿÉÒÔÁË£º
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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create table student
(
id int primary key,
name nvarchar2(50) not null,
score number not null
);
insert into student values(1,'Aaron',78);
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