原因: 由于在PLSQL Developer执行update时没有commit,oracle将该条记录锁住了. 可以通过以下办法解决: 先查询锁定记录 Sql代码 SELECT s.sid, s.serial# FROM v$locked_object lo, dba_objects ao, v$session s WHERE ao.object_id = lo.object_id AND lo.session_id = s.sid; 然后删除锁定记录 Sql代码 ALTER system KI
DECLARE num NUMBER; BEGIN SELECT COUNT(1) INTO num FROM USER_TABLES WHERE TABLE_NAME = UPPER('tableName') ; IF num > 0 THEN EXECUTE IMMEDIATE 'DROP TABLE tableName' ; END IF; END; 多表情况 declare num number; num1 number; num2 number; begin SELECT COUNT(
1.用PowerDesigner12建模,在Database—>Generate Database (或者用Ctrl+G快捷键)来生产sql语句,却提示“Generation aborted due to errors detected during the verification of the model.”的错误,截图如下: 2.解决方案------把检查模型的选项(Check Model)前的那个勾去掉即可,如图:
oracle创建表时,不支持在建表时同时增加字段注释.故采用以下方式: #创建表CREATE TABLE predict_data as ( id integer ), mid ), time date , content ), constraint predict_data primary key (id) );#字段注释comment on table predict_data is '预测表';comment on column predict_data.id is '主键';commen
创建Oracle数据库表时加上注释 CREATE TABLE t1( id varchar2(32) primary key,name VARCHAR2(8) NOT NULL, age number, ) 添加表注释: COMMENT ON table t1 IS '个人信息'; 添加字段注释: comment on column t1.id is 'id'; comment on column t1.nameis '姓名'; comment on column t1.age is '年龄
Oracle 在Drop表时的Cascade Constraints 假设A为主表(既含有某一主键的表),B为从表(即引用了A的主键作为外键).则当删除A表时,如不特殊说明,则 drop table A 系统会出现如下错误警告的信息而不会允许执行. ERROR at line 1: ORA-02449: unique/primary keys in table referenced by foreign keys 此时必须用,drop table A cascade constraints:
http://hi.baidu.com/rebooo/item/12b500b130022bf263388e69假设A为主表(既含有某一主键的表),B为从表(即引用了A的主键作为外键).则当删除A表时,如不特殊说明,则 drop table A 系统会出现如下错误警告的信息而不会允许执行. ERROR at line 1: ORA-02449: unique/primary keys in table referenced by foreign keys 此时必须用,drop table A
删表的时候碰到表忙的情况,会报错. DROP TABLE TMP_TAB_T_AGENT * ERROR at line 1: ORA-14452: attempt to create, alter or drop an index on temporary table already in USE 这个时候可以使用几个视图查看一下当前哪些SESSION正在使用 SET lines 200 pages 100 col program FOR a20 col MODULE FOR a20 col