在MySql4.0.12中,用" create table bak_name as select * from original_name"語句後
,生成的bak 表沒有主鍵及索引的,用到的時候一點要注意.可以先建一個和要備份的表結構一
樣的表back_name,用以下方法倒入數據
insert into bak_table select * from original_name 這個方法
在mysql教程中可以把已經存在的表直接通過命令復制為另一個表
方法1：create table mmm select * from bbb; 注意：這條命令要求mmm這個表在數據庫教程中
不存在
這條命令可以創建新表mmm並且bbb中的表結構以及數據和mmm完全一樣，也可以導出部分字段
create table mmm select 字段1,字段2 from bbb;
方法2：insert into mmm select * bbb; 這條語句和上一條語句實現同樣的功能，只是要求
mmm表必須在數據庫中存在
mysql>
mysql> CREATE TABLE Topic(
-> TopicID SMALLINT NOT NULL AUTO_INCREMENT PRIMARY KEY,
-> Name VARCHAR(50) NOT NULL,
-> InStock SMALLINT UNSIGNED NOT NULL,
-> OnOrder SMALLINT UNSIGNED NOT NULL,
-> Reserved SMALLINT UNSIGNED NOT NULL,
-> Department ENUM('Classical', 'Popular') NOT NULL,
-> Category VARCHAR(20) NOT NULL,
-> RowUpdate TIMESTAMP NOT NULL
-> );
Query OK, 0 rows affected (0.03 sec)mysql>
mysql>
mysql> INSERT INTO Topic (Name, InStock, OnOrder, Reserved, Department,Category) VALUES
-> ('Java', 10, 5, 3, 'Popular','Rock'),
-> ('JavaScript', 10, 5, 3,'Classical', 'Opera'),
-> ('C Sharp', 17, 4, 1, 'Popular','Jazz'),
-> ('C', 9, 4, 2,'Classical', 'Dance'),
-> ('C++', 24, 2, 5,'Classical', 'General'),
-> ('Perl', 16, 6, 8,'Classical', 'Vocal'),
-> ('Python', 2, 25, 6, 'Popular','Blues'),
-> ('Php', 32, 3, 10, 'Popular','Jazz'),
-> ('ASP.net', 12, 15, 13, 'Popular','Country'),
-> ('VB.net', 5, 20, 10, 'Popular','New Age'),
-> ('VC.net', 24, 11, 14, 'Popular','New Age'),
-> ('UML', 42, 17, 17,'Classical', 'General'),
-> ('www.java2s.com',25, 44, 28,'Classical', 'Dance'),
-> ('Oracle', 32, 15, 12,'Classical', 'General'),
-> ('Pl/SQL', 20, 10, 5,'Classical', 'Opera'),
-> ('Sql Server', 23, 12, 8,'Classical', 'General');
Query OK, 16 rows affected (0.00 sec)
Records: 16 Duplicates: 0 Warnings: 0mysql>
mysql> select * from Topic;
+---------+----------------+---------+---------+----------+------------+----------+---------------------+
| TopicID | Name | InStock | OnOrder | Reserved | Department | Category| RowUpdate |
+---------+----------------+---------+---------+----------+------------+----------+---------------------+
| 1 | Java | 10 | 5 | 3 | Popular | Rock| 2007-07-23 19:09:52 |
| 2 | JavaScript | 10 | 5 | 3 | Classical | Opera| 2007-07-23 19:09:52 |
| 3 | C Sharp | 17 | 4 | 1 | Popular | Jazz| 2007-07-23 19:09:52 |
| 4 | C | 9 | 4 | 2 | Classical | Dance| 2007-07-23 19:09:52 |
| 5 | C++ | 24 | 2 | 5 | Classical | General| 2007-07-23 19:09:52 |
| 6 | Perl | 16 | 6 | 8 | Classical | Vocal| 2007-07-23 19:09:52 |
| 7 | Python | 2 | 25 | 6 | Popular | Blues| 2007-07-23 19:09:52 |
| 8 | Php | 32 | 3 | 10 | Popular | Jazz| 2007-07-23 19:09:52 |
| 9 | ASP.net | 12 | 15 | 13 | Popular | Country| 2007-07-23 19:09:52 |
| 10 | VB.net | 5 | 20 | 10 | Popular | New Age| 2007-07-23 19:09:52 |
| 11 | VC.net | 24 | 11 | 14 | Popular | New Age| 2007-07-23 19:09:52 |
| 12 | UML | 42 | 17 | 17 | Classical | General| 2007-07-23 19:09:52 |
| 13 | www.java2s.com | 25 | 44 | 28 | Classical | Dance| 2007-07-23 19:09:52 |
| 14 | Oracle | 32 | 15 | 12 | Classical | General| 2007-07-23 19:09:52 |
| 15 | Pl/SQL | 20 | 10 | 5 | Classical | Opera| 2007-07-23 19:09:52 |
| 16 | Sql Server | 23 | 12 | 8 | Classical | General| 2007-07-23 19:09:52 |
+---------+----------------+---------+---------+----------+------------+----------+---------------------+
16 rows in set (0.00 sec)mysql>
mysql> CREATE TABLE Topic2
-> (
-> TopicID SMALLINT NOT NULL PRIMARY KEY,
-> Name VARCHAR(50) NOT NULL,
-> InStock SMALLINT UNSIGNED NOT NULL
-> )
-> SELECT TopicID, Name, InStock
-> FROM Topic
-> WHERE Category='Blues' OR Category='Jazz';
Query OK, 3 rows affected (0.01 sec)
Records: 3 Duplicates: 0 Warnings: 0mysql>
mysql> select * from Topic2;
+---------+---------+---------+
| TopicID | Name | InStock |
+---------+---------+---------+
| 3 | C Sharp | 17 |
| 7 | Python | 2 |
| 8 | Php | 32 |
+---------+---------+---------+
3 rows in set (0.00 sec)
