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MySQL

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MySQL

您需要进行三向联接:

CREATE TABLE new_table ASSELECt p.*, d.content AS ageFROM people AS pJOIN details AS d ON d.person_id = p.idJOIN taxonomy AS t ON t.id = d.detail_idWHERe t.taxonomy = 'age'

演示

或者,如果您已经创建了表,则可以执行以下操作:

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 ageFROM people AS pJOIN details AS d ON d.person_id = p.idJOIN taxonomy AS t ON t.id = d.detail_idWHERe t.taxonomy = 'age'

要获得多个属性,您必须分别为每个属性将详细信息和分类表联接在一起:

CREATE TABLE new_table ASSELECt p.*, d1.content AS age, d2.content AS gender, d3.content AS heightFROM people AS pJOIN details AS d1 ON d1.person_id = p.idJOIN taxonomy AS t1 ON t1.id = d1.detail_idJOIN details AS d2 ON d2.person_id = p.idJOIN taxonomy AS t2 ON t2.id = d2.detail_idJOIN details AS d3 ON d3.person_id = p.idJOIN taxonomy AS t3 ON t3.id = d3.detail_idWHERe t1.taxonomy = 'age' AND t2.taxonomy = 'gender' AND t3.taxonomy = 'height'


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