数据库中更新或插入表记录

会碰到下列场景：当记录，在目标表中存在就更新值，若不存在就插入记录。

一、示例数据

-- test_source 数据源表

CREATE TABLE `test_source` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `BWKEY` varchar(255) DEFAULT NULL,
  `MATNR` varchar(255) DEFAULT NULL,
  `VERPR` double(255,0) DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `sBWKEY` (`BWKEY`,`MATNR`)
) ENGINE=InnoDB AUTO_INCREMENT=7 DEFAULT CHARSET=utf8

INSERT INTO `zjkywms`.`test_source`(`id`, `BWKEY`, `MATNR`, `VERPR`) VALUES (1, '2105', 'A', 1);
INSERT INTO `zjkywms`.`test_source`(`id`, `BWKEY`, `MATNR`, `VERPR`) VALUES (2, '2105', 'B', 2);
INSERT INTO `zjkywms`.`test_source`(`id`, `BWKEY`, `MATNR`, `VERPR`) VALUES (3, '2105', 'C', 3);
INSERT INTO `zjkywms`.`test_source`(`id`, `BWKEY`, `MATNR`, `VERPR`) VALUES (4, '2106', 'A', 4);
INSERT INTO `zjkywms`.`test_source`(`id`, `BWKEY`, `MATNR`, `VERPR`) VALUES (5, '2106', 'B', 5);
INSERT INTO `zjkywms`.`test_source`(`id`, `BWKEY`, `MATNR`, `VERPR`) VALUES (6, '2106', 'C', 6);

-- test_target 目标表/待更新或插入

CREATE TABLE `test_target` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `BWKEY` varchar(255) DEFAULT NULL,
  `MATNR` varchar(255) DEFAULT NULL,
  `VERPR` double(255,0) DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `tBWKEY` (`BWKEY`,`MATNR`)
) ENGINE=InnoDB AUTO_INCREMENT=4 DEFAULT CHARSET=utf8

INSERT INTO `zjkywms`.`test_target`(`id`, `BWKEY`, `MATNR`, `VERPR`) VALUES (1, '2105', 'A', 7);
INSERT INTO `zjkywms`.`test_target`(`id`, `BWKEY`, `MATNR`, `VERPR`) VALUES (2, '2106', 'C', 6);
INSERT INTO `zjkywms`.`test_target`(`id`, `BWKEY`, `MATNR`, `VERPR`) VALUES (3, '2107', 'Z', 9);

二、update + insert 二步操作

-- 待更新的记录
SELECT * from test_target t inner JOIN test_source s on s.BWKEY=t.BWKEY and s.MATNR=t.MATNR;
-- update test_target t inner JOIN test_source s on s.BWKEY=t.BWKEY and s.MATNR=t.MATNR set t.VERPR=s.VERPR

-- 待插入的记录
-- insert into test_target (BWKEY,MATNR,VERPR)
 SELECT s.BWKEY,s.MATNR,s.VERPR from test_source s where not exists (select 1 from test_target t where s.BWKEY=t.BWKEY and s.MATNR=t.MATNR);

效果

mysql> select * from test_target;
+----+-------+-------+-------+
| id | BWKEY | MATNR | VERPR |
+----+-------+-------+-------+
|  1 | 2105  | A     |     1 |
|  2 | 2106  | C     |     6 |
|  5 | 2107  | Z     |     9 |
|  6 | 2105  | B     |     2 |
|  7 | 2105  | C     |     3 |
|  8 | 2106  | A     |     4 |
|  9 | 2106  | B     |     5 |
+----+-------+-------+-------+
7 rows in set (0.03 sec)

记录ID：1是更新记录，原值是7；6~9是插入记录。

三、Oracle一步操作

<待完成>

四、MySQL一步操作

<待完成>

原文地址：https://www.cnblogs.com/Tty725/p/11669952.html