PL/SQL number型数据
PL/SQL number型数据
number( ,)
精度p取值范围1~38
有效位s取值范围-84~127
最高整数位数=p-s
s正数,小数点右边指定位置开始四舍五入
s负数,小数点左边指定位置开始四舍五入
s是0或者未指定,四舍五入到最近整数
当p小于s时候,表示数字是绝对值小于1的数字,且从小数点右边开始的前s-p 位必须是0,保留s位小数。
--num_test start------------------------------------------------
Connected to Oracle9i Enterprise Edition Release 9.0.1.1.1
Connected as aspire
SQL>
SQL> SET linesize 1000;
SQL> CREATE TABLE hjm_num_test
2 (a NUMBER,
3 b NUMBER(5,2),
4 c NUMBER(5,-2),
5 d NUMBER(5,0),
6 e NUMBER(5),
7 f NUMBER(2,5));
Table created
SQL> INSERT INTO hjm_num_test
2 (a,b,c,d,e,f) VALUES(123.3333,123.3333,123.3333,123.3333,123.3333,-0.0003);
1 row inserted
SQL> INSERT INTO hjm_num_test
2 (a,b,c,d,e,f) VALUES(197.9333,197.9333,197.9333,197.9333,197.9333,0.00012567);
1 row inserted
SQL> COMMIT;
Commit complete
SQL> SELECT * FROM hjm_num_test;
(在pl/sql dev sql窗口显示)
--num_test end--------------------------------------------------------
似乎结果很正确,可是现在出来一个问题,当我不在pl/sql dev窗口运行,我在isqlplus中运行,结果就有点不一样了,注意,第1行的F列:
(在isqlplus中显示)
它舍去了末尾的0!在sqlplus下测试也是同样的效果。
不过本人的意向应该是还是保留那个0的,因为number(2,5)它毕竟指定了有效位是5位。

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