MySQL在READ-COMMITTED隔离级别下，出现了insert阻塞update的情况，但同样的情况下，Oracle的insert则不会阻...
在MySQL中,如果你想要实现“如果存在就更新(UPDATE),如果不存在就插入(INSERT)”的逻辑,可以使用以下几种方法: 方法一:使用 INSERT ... ON DUPLICATE KEY UPDATE 这种方法适用于你的表中存在唯一索引或主键约束的情况。当尝试插入的数据与现有数据的唯一索引或主键冲突时,会执行UPDATE操作。 sql INSERT INTO your_...
Re: Update record if exists else insert. 882 Paul Keddie October 12, 2019 10:05PM Sorry, you can't reply to this topic. It has been closed. Content reproduced on this site is the property of the respective copyright holders. It is not reviewed in advance by Oracle and does not necess...
'ip_addess' 列是唯一的,MSSQL 和 MySQL 的表结构相同。 是否有可以在两种数据库类型中执行 IF INSERT ELSE UPDATE 的语法? 是的,我做(PDO)参数绑定,xxx只是为了缩短代码片段。 是的,如果我在两个查询(首先选择,然后插入或更新)中执行相同的语法,我可以使用相同的语法,但我想避免(希望)不必要的查询。
If the record exists, it is updated, else inserted. http://dev.mysql.com/doc/refman/5.0/en/replace.html Anonymous February 21, 2008 The comment has been removed Anonymous February 21, 2008 Looking into the MySql documentation a little more I found this statement: INSERT ... ON DUPLICATE ...
If the record exists, it is updated, else inserted. http://dev.mysql.com/doc/refman/5.0/en/replace.html Anonymous February 21, 2008 The comment has been removed Anonymous February 21, 2008 Looking into the MySql documentation a little more I found this statement: INSERT ... ON DUPLICATE ...
for insert,update as if not exists(select 1 from deleted) begin /*deleted表无记录,是新增*/ end if not exists(select 1 from inserted) begin /*inserted表无记录,是删除*/ end else begin /*是更新*/ end go eg: create trigger Add_Del_Update on tab1 ...
我们有时需要对一个表进行更新操作,当某条记录不存在的时候进行插入操作,存在的时候更新纪录。通常我们使用if(exists(select ...)update...else insert,这样进行两遍表扫描,效率很低,在Oracle 9i以上有一个关键字merge,我们使用它就可以了。merge into 需要两个标操作,我们利用dual merge...
-- DML语句对表数据进行insert[增], delete[删], update[改], merge[合并, Mysql不可用], replce into[删+增/增] -- CREATE TABLE IF NOT EXISTS users2 ( -- `id` INT(11) NOT NULL
Re: Update record if exists else insert. 872 Paul Keddie October 12, 2019 10:05PM Sorry, you can't reply to this topic. It has been closed. Content reproduced on this site is the property of the respective copyright holders. It is not reviewed in advance by Oracle and does not necess...