Question

我创建了以下表格：

create table AandB (
        code              varchar(9),
        total             number,
        CONSTRAINT pk_code PRIMARY KEY (code)
);

create table A (
        codeA              varchar(9),
        numberA              number,
        CONSTRAINT pk_codeA PRIMARY KEY (codeA)
);

create table B (
        codeB              varchar(9),
        numberB            number,
        CONSTRAINT pk_codeB PRIMARY KEY (codeB)
);

我插入了以下数据：

insert into AandB(code) values('0x1');
insert into AandB(code) values('0x2');
insert into AandB(code) values('0x3');

insert into A(codeA, numberA) values('0x1',5);
insert into A(codeA, numberA) values('0x2',6);
insert into A(codeA, numberA) values('0x3',1);

insert into B(codeB, numberB) values('0x1',8);
insert into B(codeB, numberB) values('0x2',10);
insert into B(codeB, numberB) values('0x3',12);

问题是：如何在列＃34; total＆＃34;中插入numberA + numberB表格＃34; AandB＆＃34;，即：

0X1 = 13

0X2 = 16

0X3 = 13

感谢您提出任何建议或答案，祝您有个愉快的一天！

Answer 1

好吧，只需根据AandB和A之间的联接更新B表

UPDATE AandB ab
SET ab.total = (SELECT a.numberA + b.numberB
                FROM A
                INNER JOIN B
                 ON(a.codeA = b.codeB)
                WHERE a.codeA = ab.code)

如果A和B表不一定包含所有AandB代码，那么您应该添加一个where子句来过滤它们：

UPDATE AandB ab
SET ab.total = (SELECT a.numberA + b.numberB
                FROM A
                INNER JOIN B
                 ON(a.codeA = b.codeB)
                WHERE a.codeA = ab.code)
WHERE EXISTS(SELECT 1 FROM A
             INNER JOIN B
              ON(a.codeA = b.codeB)
             WHERE a.codeA = ab.code)

如何在Oracle中插入两个表的总和？

1 个答案: