本节涉及SQL语句: -- MYSQL 基础操作 1.插入insert语句 INSERT INTO t_dept(deptno,dname,loc) VALUES(70,"后勤部","北京"),(80,"保安部","北京"); 2.向技术部插入一条员工信息 INSERT INTO t_emp (empno,ename,job,mgr,hiredate,sal,comm,deptno) VALUES(8001,"刘娜&
想要插入一条数据,要避免重复插入,又不想折腾两回数据库连接操作,可以参考如下办法. INSERT INTO table(column1,column2,column3 ...columnN) SELECT value1,value2,value3 ...valueN FROM dual WHERE NOT EXISTS( SELECT * FROM table WHERE value = ? ); dual是为了构建查询语句而存在的表,Oracle中很常见,配合INSERT ... SELECT
INSERT INTO dbo.[T_DabaoTemp] ([PType] ,[pID] ,[NewVersion] ,[ParentCode] ,[Addtime]) select 0,5,'2.0.1','0_3',GETDATE() WHERE not exists ( select 1 from [T_DabaoTemp] where [PType]=0 and [pID]=5 and [NewVersi
当通过task 插入多条数据时报错. DBcontext 不是线程安全的, 如果是WebAPI 为每个请求创建DbContext 部分解释: http://stackoverflow.com/questions/28106267/insert-into-dbcontext-multithreading# DbContext isn't thread-safe. One context and many threads - it is a bad practice. It is best to c