java - 外键约束失败 该怎么解决

Question

WARNING]
org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.springframework.dao.DataIntegrityViolationException:

Error updating database. Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Cannot add or update a child row: a foreign key constraint fails (lgip.tb_intention, CONSTRAINT fk_intention_user FOREIGN KEY (firm_id) REFERENCES tb_user (id))

The error may involve com.nstc.lgip.idao.TbIntentionMapper.insert-Inline

The error occurred while setting parameters

SQL: insert into tb_intention (id, firm_id, industry_type ) values (?, ?, ? )

Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Cannot add or update a child row: a foreign key constraint fails (lgip.tb_intention, CONSTRAINT fk_intention_user FOREIGN KEY (firm_id) REFERENCES tb_user (id))

; SQL []; Cannot add or update a child row: a foreign key constraint fails (lgip.tb_intention, CONSTRAINT fk_intention_user FOREIGN KEY (firm_id) REFERENCES tb_user (id)); nested exception is com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Cannot add or update a child row: a foreign key constraint fails (lgip.tb_intention, CONSTRAINT fk_intention_user FOREIGN KEY (firm_id) REFERENCES tb_user (id))

Answer 1

The firm_id you inserted does not have a corresponding id in the tb_user table. . . . . . .

Answer 2

The foreign key table performs a left link query on the primary key table and finds that some IDs do not exist in the primary key table. You can then decide whether to delete or retain them