您有两个表:1. docs 2. doc_val
重点是 table : doc_val ,它具有来自 table docs 的 doc_id FK ,字段标准将成为我们的条件。
Mysql 架构:
CREATE TABLE IF NOT EXISTS `docs` (
`id` int(6) unsigned NOT NULL,
`rev` int(3) unsigned NOT NULL,
`content` varchar(200) NOT NULL,
PRIMARY KEY (`id`)
) DEFAULT CHARSET=utf8;
CREATE TABLE IF NOT EXISTS `doc_val` (
`id` int(6) unsigned NOT NULL,
`doc_id` int(6) unsigned NOT NULL,
`val` int(3) unsigned NOT NULL,
`type` varchar(2) NOT NULL,
`criteria` varchar(2) NOT NULL,
PRIMARY KEY (`id`)
) DEFAULT CHARSET=utf8;
INSERT INTO `docs` (`id`, `rev`, `content`) VALUES
('1', '1', 'The earth is flat'),
('2', '1', 'One hundred angels can dance on the head of a pin'),
('3', '1', 'The earth is flat and rests on a bull\'s horn'),
('4', '4', 'The earth is like a ball.');
INSERT INTO `doc_val` (`id`, `doc_id`, `val`, `type`, `criteria`) VALUES
('1', '1', 100, 'D', 'L'),
('2', '1', 101, 'D', 'L'),
('3', '1', 80, 'H', 'L'),
('4', '2', 10, 'H', 'S'),
('5', '2', 90, 'H', 'L'),
('6', '3', 100, 'D', 'L'),
('7', '3', 100, 'D', 'L');
预期输出: