ON DUPLICATE KEY UPDATE id=id (it won't trigger row update even though id is assigned to itself). If you don't care about errors (conversion errors, foreign key errors) and autoincrement field exhaustion (it's incremented even if the row is not inserted due to duplicate key), then use...
As I said above, ON DUPLICATE KEY does nothing unless you try to insert a value that conflicts with a primary or unique key for a row that already exists in the table. But in this case you aren't conflicting, you're always generating a new ID value. So it inserts a new row. If ...
往数据库中插入记录时,如果发生唯一索引值冲突,insert on duplicate允许进行进一步的crud操作。伪代码如下: insert recordIFexist duplicate recordTHENdosomething on duplicated rowsELSEdonothingENDIF 具体用法 先初始化将要用到的表跟数据 createtablet1(idbigintprimarykeyauto_increment,aintegerunique,bintegerdefault999...
idbigintprimarykeyauto_increment, aintegerunique, bintegerdefault999);INSERTINTOtest_insert_on_dup_update(id, a)VALUES(1,1);INSERTINTOtest_insert_on_dup_update(id, a)VALUES(5,5);INSERTINTOtest_insert_on_dup_update(id, a)VALUES(10,10);insertintot1(a,b)values(1,199)onduplicateupdateb=...
(flags & BTR_NO_LOCKING_FLAG) { /* Do nothing if no-locking is set */ err = DB_SUCCESS; } else if (trx->duplicates) { /* If the SQL-query will update or replace duplicate key we will take X-lock for duplicates ( REPLACE, LOAD DATAFILE REPLACE, INSERT ON DUPLICATE KEY UPDATE)...
ON DUPLICATE KEY UPDATE insert ignore into users(user_id,user_name) values("111","naruto"),("222","sasuke") on duplicate key update user_name=values(user_name); ～～～ 回到顶部 自己的其他文档 并发处理IO任务与MySQL中ON DUPLICATE KEY UPDATE的使用...
@return true on success, false on failure */ static MY_ATTRIBUTE((warn_unused_result)) ibool page_zip_dir_decode( const page_zip_des_t *page_zip, /*!< in: dense page directory on compressed page */ page_t *page, /*!< in: compact page with valid header; out: trailer and ...
INSERT INTO example (a, b, c) VALUES (1,2,3) ON DUPLICATE KEY UPDATE a = VALUES(a), b = VALUES(b), c = VALUES(c); If you consider (a,b,c) a unique key, there are two things you need to do First, add a unique index ALTER TABLE example ADD UNIQUE KEY abc_ndx (...
I had a script which worked perfectly fine on my old hosting- INSERT INTO `database`.`table` (`UUID`, `UpdateDate`, `JoinDate`) VALUES ('$uuid',NOW(),NOW()) ON DUPLICATE KEY UPDATE `UpdateDate` = NOW() The problem is it doesnt work any more on my new server. The problem ...
(20) not null, dpt_id int, constraint fk_name foreign key(dpt_id) references department(id) on delete cascade on update cascade )engine=innodb; #先往父表department中插入记录 insert into department values (1,'欧德博爱技术有限事业部'), (2,'艾利克斯人力资源部'), (3,'销售部'); #再往...