DBMS_RANDOM各函数使用

1、包定义：

sql>desc dbms_random

Element Type

---------- ---------

SEED PROCEDURE

VALUE FUNCTION

NORMAL FUNCTION

STRING FUNCTION

INITIALIZE PROCEDURE

RANDOM FUNCTION

TERMINATE PROCEDURE

NUM_ARRAY TYPE

2、使用举例：

a、value() 用于返回两个数值之间的随机数，value（low，high）

SQL> select dbms_random.value() from dual;

DBMS_RANDOM.VALUE() 默认是从0到1间的数

-------------------

0.0536824248407651

SQL> select dbms_random.value(10,100) from dual;



DBMS_RANDOM.VALUE(10,100)

-------------------------

29.2420951206225

b、random() 返回的值介于2的31次方和-2的31次方之间的整形数值

SQL> select dbms_random.random() from dual;

DBMS_RANDOM.RANDOM()

--------------------

2071097056

SQL> select dbms_random.random() from dual;

DBMS_RANDOM.RANDOM()

--------------------

-1589187025

c、string('parameter',length)

SQL> select dbms_random.string('a',10)
from dual; --all返回不分大小写的字母字符串

DBMS_RANDOM.STRING('A',10)

--------------------------------------------------------------------------------

eDvKaqNWII

SQL> select dbms_random.string('u',10) from dual;
--upper返回大写字母字符串

DBMS_RANDOM.STRING('U',10)

--------------------------------------------------------------------------------

KPGNYTWDGA

SQL> select dbms_random.string('l',10) from dual; --little小写字母

DBMS_RANDOM.STRING('L',10)

--------------------------------------------------------------------------------

zehtdserww

SQL> select dbms_random.string('x',10) from dual;
---大写字母加数字

DBMS_RANDOM.STRING('X',10)

--------------------------------------------------------------------------------

3Z7DBA4S8I

SQL> select dbms_random.string('p',10)
from dual; --print 所有可以打印的字符

DBMS_RANDOM.STRING('P',10)

--------------------------------------------------------------------------------

Vj|2~cWM"K

SQL> select dbms_random.string('p',10) from dual;

DBMS_RANDOM.STRING('P',10)

--------------------------------------------------------------------------------

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