mySQL – 使用三个表中的数据和列创build一个新表
我正在尝试创build一个新的表，它将包含三个现有表中的选定数据。
现有的三个表格设置如下，我期望的结果是在底部：
people id last_name first_name email 1 Smith Fred Fred@.. 2 Jones Tom Tom@.. 3 Doe Jane Jane@.. taxonomy id taxonomy 1 age 2 gender 3 height details id person_id detail_id content 1 1 1 36 2 1 2 M 3 1 3 5'10" 4 2 1 29 5 2 2 M 6 2 3 6'3" 7 3 1 27 8 3 2 F 9 3 3 5'8" New Table id last_name first_name email age 1 Smith Fred Fred@.. 36 2 Jones Tom Tom@.. 29 3 Doe Jane Jane@.. 27 在此先感谢您的帮助！
你需要做一个3路联接：
CREATE TABLE new_table AS SELECT p.*, d.content AS age FROM people AS p JOIN details AS d ON d.person_id = p.id JOIN taxonomy AS t ON t.id = d.detail_id WHERE t.taxonomy = 'age'
DEMO
或者如果你已经创build了表格，你可以这样做：
INSERT INTO new_table (id, last_name, first_name, email, age) SELECT p.id, p.last_name, p.first_name, p.email, d.content AS age FROM people AS p JOIN details AS d ON d.person_id = p.id JOIN taxonomy AS t ON t.id = d.detail_id WHERE t.taxonomy = 'age'
要获得多个属性，您必须为每个属性分别join详细信息和分类表：
CREATE TABLE new_table AS SELECT p.*, d1.content AS age, d2.content AS gender, d3.content AS height FROM people AS p JOIN details AS d1 ON d1.person_id = p.id JOIN taxonomy AS t1 ON t1.id = d1.detail_id JOIN details AS d2 ON d2.person_id = p.id JOIN taxonomy AS t2 ON t2.id = d2.detail_id JOIN details AS d3 ON d3.person_id = p.id JOIN taxonomy AS t3 ON t3.id = d3.detail_id WHERE t1.taxonomy = 'age' AND t2.taxonomy = 'gender' AND t3.taxonomy = 'height'
