SQLServer 和Oracle常用函数对比
1
.绝对值
S:
select
abs
(
-
1
) value
O:
select
abs
(
-
1
) value
from
dual
2
.取整(大)
S:
select
ceiling
(
-
1.001
) value
O:
select
ceil(
-
1.001
) value
from
dual
3
.取整（小）
S:
select
floor
(
-
1.001
) value
O:
select
floor
(
-
1.001
) value
from
dual
4
.取整（截取）
S:
select
cast
(
-
1.002
as
int
) value
O:
select
trunc(
-
1.002
) value
from
dual
5
.四舍五入
S:
select
round
(
1.23456
,
4
) value
1.23460
O:
select
round
(
1.23456
,
4
) value
from
dual
1.2346
6
.e为底的幂
S:
select
Exp
(
1
) value
2.7182818284590451
O:
select
Exp
(
1
) value
from
dual
2.71828182
7
.取e为底的对数
S:
select
log
(
2.7182818284590451
) value
1
O:
select
ln(
2.7182818284590451
) value
from
dual;
1
8
.取10为底对数
S:
select
log10
(
10
) value
1
O:
select
log
(
10
,
10
) value
from
dual;
1
9
.取平方
S:
select
SQUARE
(
4
) value
16
O:
select
power
(
4
,
2
) value
from
dual
16
10
.取平方根
S:
select
SQRT
(
4
) value
2
O:
select
SQRT
(
4
) value
from
dual
2
11
.求任意数为底的幂
S:
select
power
(
3
,
4
) value
81
O:
select
power
(
3
,
4
) value
from
dual
81
12
.取随机数
S:
select
rand
() value
O:
select
sys.dbms_random.value(
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