KEY`ref_num` (`ref_num`), CONSTRAINT`ref_num_ibfk_1`FOREIGNKEY(`ref_num`)REFERENCES`solution_table` (`num1`) ) ref_table有个外键约束指向表solution_table。按照字母顺序,mysqldump会先dump出ref_table。在还原过程中,就会遇到如下的错误: 1 ERROR
mysql> insert into students values('张一',1,1); ERROR 1452 (23000): Cannot add or update a child row: a foreign key constraint fails (`test`.`students`, CONSTRAINT `students_ibfk_1` FOREIGN KEY (`classid`) REFERENCES `class` (`id`)) # 报错,因为此时班级表中没有 id 为 1 的记录 ...
mysql> insert into student2(id,name,class_id) values(1,'alex', 1); ERROR 1452 (23000): Cannot add or update a child row: a foreign key constraint fails (`testdb`.`student2`, CONSTRAINT `fk_class_key` FOREIGN KEY (`class_id`) REFERENCES `class` (`id`)) mysql> insert into clas...
ERROR 1452 (23000): Cannot add or update a child row: a foreign key constraint fails (`mail3x`.`james_mail`, CONSTRAINT `james_mail_ibfk_1` FOREIGN KEY (`MAILBOX_ID`) REFERENCES `james_mailbox` (`MAILBOX_ID`) ON DELETE CASCADE) ...
mysql considers there is no table named `webmasters` (lower case) and issues an error, like 1452: Cannot add or update a child row: a foreign key constraint fails... How to repeat: Server settings must be lower_case_table_names = 2 Execute following SQL: CREATE TABLE `Webmasters` ( ...
前提是你的电脑中配置了MySQL的环境变量,某则需要在MySQL的安装目录中找到mysqldump 程序入口。 2022-08-01_143245.png 但是当我在Java代码中使用Runtime.getRuntime().exec("cmd")执行这个SQL语句时,process.waitFor()返回了6,是一个错误的结果。
ERROR 1452 (23000): Cannot add or update a child row: a foreign key constraint fails (`Orange/pc`, CONSTRAINT `pc_ibfk_1` FOREIGN KEY (`cpumodel`) REFERENCES `parts` (`cpu`)) 四、外键的删除 这个fk_pc就是表pc的外键,用来为删除外键定义用的,如下所示: ...
2017-06-09T08:09:24.559284Z 0 [Warning] InnoDB: Creating foreign key constraint system tables. 2017-06-09T08:09:25.174319Z 0 [Warning] No existing UUID has been found, so we assume that this is the first time that this server has been started. Generating a new UUID: f3a3b10f-4cea-...