有这样一张表: create table tb_lostid( id number(6,0) primary key not null, name nvarchar2(20) not null ) 可以这样给它充值: insert into tb_lostid select rownum, dbms_random.string('*',dbms_random.value(1,20)) from dual connect by level<10000 然后删掉几条记录,以此来模拟误操作: dele
使用ORM框架ORMLITE有一段时间,今天在操作一个对象的时候,重新运行报错如下: Must specify one of id, generatedId, and generatedIdSequence with Id 翻译:意思大概也就是必须要有其中一个 id / generatedId / generatedIdSequence 再上下我的对象的源码: @DatabaseField(columnName = PaymentTempUploadTable.COLUMN_ID, id =
目录(?)[-] 有一个相同两个不同相同 Written by Mattt Thompson on Dec 10th 2012 一什么是instancetype 二关联返回类型related result types 三instancetype作用 作用 好处 四instancetype和id的异同 相同点 不同点 有一个相同两个不同.相同 Written by Mattt Thompson on Dec 10th, 2012 Objective-C is a rapidly evolvin
假设你数据库有个A表: ID NAME 1 aaa 2 bbb 3 ccc 4 ddd 需求:给你几个ID,返回A表中不存在的ID? 例如提交1,2,8,9 返回8,9 select B.id as id from dual union as id from dual union as id from dual union as id from dual ) B left join A on A.id = B.id where A.id is null;
create or replace trigger t before update on test5 for each rowbegin insert into test55 values (:old.id,:old.name);end ; -------------------------------------------------------------------------------------- --表中插入数据时ID自动增长 create table ttt (id numbe
有一个相同两个不同.相同 Written by Mattt Thompson on Dec 10th, Objective-C is a rapidly evolving language, in a way that you just don't see in established programming languages. ARC, object literals, subscripting, blocks: in the span of just three years, so muc
