在oracle数据库中,要求两个字段的和要怎么写sql语句_工具

在oracle数据库中,要求两个字段的和可以用sql语句（前提是两个字段都是数字型）：

SELECT num1+num2 AS num FROM table_name;

其中num1、num2是要求和的两个字段，num是新命名的和字段，table_name是要查询的表名。

扩展资料：

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1，如果都是数字类型的直接把这两个字段相加

select

a+b as ab

from S ;

或者你的意思是 select sum(a+b) from S;

2，如果是不同的字段类型就不能求和了，但是可以使用“||”或者CONCAT()函数

21 select a||b from S;

22 select concat(a,b) from S;

参考资料来源：百度百科-Oracle数据库

可以创建一个函数，然后来求和。

1先创建一个函数

CREATE OR REPLACE FUNCTION res_exp( p_Express varchar)

RETURN NUMBER

v_RESULT NUMBER;

v_Sql varchar(200);

BEGIN

v_Sql := 'SELECT ' || p_Express || ' FROM dual';

EXECUTE IMMEDIATE ( v_Sql ) INTO v_RESULT ;

RETURN v_RESULT;

END res_exp;

2通过正则表达式，将PARA_VALUE转为求和表达式，我这里用自己的例子来做：

with t as (

select 'item1=1,item2=2,item3=3' aa from dual

union all

select 'item1=1,item2=2,item3=3' aa from dual

)

SELECT res_exp(regexp_replace(regexp_REPLACE(aa, ',item[[:digit:]]=', '+'), 'item[[:digit:]]=', '')) res

FROM t

你的可以这样写

SELECT res_exp(regexp_replace(regexp_REPLACE(PARA_VALUE, ',item[[:digit:]]=', '+'), 'item[[:digit:]]=', '')) res

FROM 你的表名

SELECT CASE

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '00:00:00' AND

'00:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '01:00:00' AND

'01:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '02:00:00' AND

'02:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '03:00:00' AND

'03:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '04:00:00' AND

'04:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '05:00:00' AND

'05:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '06:00:00' AND

'06:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '07:00:00' AND

'07:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '08:00:00' AND

'08:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '09:00:00' AND

'09:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '10:00:00' AND

'10:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '11:00:00' AND

'11:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '12:00:00' AND

'12:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '13:00:00' AND

'13:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '14:00:00' AND

'14:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '15:00:00' AND

'15:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '16:00:00' AND

'16:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '17:00:00' AND

'17:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '18:00:00' AND

'18:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '19:00:00' AND

'19:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '20:00:00' AND

'20:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '21:00:00' AND

'21:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '22:00:00' AND

'22:59:59' THEN

WHEN TO_CHAR(START_TIME, 'HH24:mi:ss') BETWEEN '23:00:00' AND

'23:59:59' THEN

END TIME_NUM,

SERV_NUMBER,

SUM(A) + SUM(B) + SUM(C) TOTAL

FROM TABLE

GROUP BY CASE