数字

加法。

SELECT 1 + 2 AS result;

result
3

(1 row)

SELECT 0.1 + 0.2 AS result;

result
0.3

(1 row)

减法。

SELECT 7 - 2 AS result;

result
5

(1 row)

SELECT 0.7 - 0.2 AS result;

result
0.5

(1 row)

乘法。

SELECT 3 * 4 AS result;

result
12

(1 row)

SELECT 0.3 * 0.4 AS result;

result
0.12

(1 row)

除法。

SELECT CAST(8 AS NUMERIC)/ 2 AS result;

result
4.0000000000000000

(1 row)

SELECT CAST(7 AS NUMERIC)/ 2 AS result;

result
3.5000000000000000

(1 row)

取整。

SELECT 8 / 2 AS result;

result
4

(1 row)

SELECT 7 / 2 AS result;

result
3

(1 row)

取余。

SELECT 8 % 2 AS result;

result
0

(1 row)

SELECT 7 % 2 AS result;

result
1

(1 row)