刪除表
TRUNCATE TABLE table_name--------不刪除表,只截斷表
DROP TABLE table_name-------整個表都刪除
TRUNCATE TABLE table_name--------不刪除表,只截斷表
DROP TABLE table_name-------整個表都刪除
2015-07-31
復制表數據:
1.在建表時復制:
create table table_new as select column1,...|* from table_old;
2.在添加數據是復制:
insert into table_name [(column1,...)] select column1,...|* from table_old;
1.在建表時復制:
create table table_new as select column1,...|* from table_old;
2.在添加數據是復制:
insert into table_name [(column1,...)] select column1,...|* from table_old;
2015-07-29
操作表中是數據:
1.添加數據
insert into table_name(column1,column2,...) values(value1,value2,...);
* sysdate 獲取當前日期(系統函數)
2.向表中添加默認值:
alter table table_name modify email default value;
。。。
1.添加數據
insert into table_name(column1,column2,...) values(value1,value2,...);
* sysdate 獲取當前日期(系統函數)
2.向表中添加默認值:
alter table table_name modify email default value;
。。。
2015-07-29
修改表:
4.修改字段名:alter table table_name rename column column to new_column_name;
5.修改表名:rename table_name to new_table_name;
6.1>刪除表中全部數據 truncate table table_name;
2>刪除整張表數據 drop table table_name;
4.修改字段名:alter table table_name rename column column to new_column_name;
5.修改表名:rename table_name to new_table_name;
6.1>刪除表中全部數據 truncate table table_name;
2>刪除整張表數據 drop table table_name;
2015-07-29
修改表:
1.添加字段:alter table table_name add column_name datatype;
2.修改數據類型:alter table table_name modify column_name datatype;
3.刪除字段:alter table table_name drop column column_name;
1.添加字段:alter table table_name add column_name datatype;
2.修改數據類型:alter table table_name modify column_name datatype;
3.刪除字段:alter table table_name drop column column_name;
2015-07-29