备份数据库某些字符或某些行

备份数据库某些字符或某些行

保存表中所有为M的数据
例:

 MariaDB [hellodb]> SELECT * FROM students;
+-------+---------------+-----+--------+---------+-----------+
| StuID | Name          | Age | Gender | ClassID | TeacherID |
+-------+---------------+-----+--------+---------+-----------+
|     1 | Shi Zhongyu   |  22 | M      |       2 |         3 |
|     2 | Shi Potian    |  22 | M      |       1 |         7 |
|     3 | Xie Yanke     |  53 | M      |       2 |        16 |
|     4 | Ding Dian     |  32 | M      |       4 |         4 |
|     5 | Yu Yutong     |  26 | M      |       3 |         1 |
|     6 | Shi Qing      |  46 | M      |       5 |      NULL |
|     7 | Xi Ren        |  19 | F      |       3 |      NULL |
|     8 | Lin Daiyu     |  17 | F      |       7 |      NULL |
|     9 | Ren Yingying  |  20 | F      |       6 |      NULL |
|    10 | Yue Lingshan  |  19 | F      |       3 |      NULL |
|    11 | Yuan Chengzhi |  23 | M      |       6 |      NULL |
|    12 | Wen Qingqing  |  19 | F      |       1 |      NULL |
|    13 | Tian Boguang  |  33 | M      |       2 |      NULL |
|    14 | Lu Wushuang   |  17 | F      |       3 |      NULL |
|    15 | Duan Yu       |  19 | M      |       4 |      NULL |
|    16 | Xu Zhu        |  21 | M      |       1 |      NULL |
|    17 | Lin Chong     |  25 | M      |       4 |      NULL |
|    18 | Hua Rong      |  23 | M      |       7 |      NULL |
|    19 | Xue Baochai   |  18 | F      |       6 |      NULL |
|    20 | Diao Chan     |  19 | F      |       7 |      NULL |
|    21 | Huang Yueying |  22 | F      |       6 |      NULL |
|    22 | Xiao Qiao     |  20 | F      |       1 |      NULL |
|    23 | Ma Chao       |  23 | M      |       4 |      NULL |
|    24 | Xu Xian       |  27 | M      |    NULL |      NULL |
|    25 | Sun Dasheng   | 100 | M      |    NULL |      NULL |
+-------+---------------+-----+--------+---------+-----------+
25 rows in set (0.01 sec)

过滤出Gender M
如:

MariaDB [hellodb]> SELECT * FROM students WHERE Gender='M';
+-------+---------------+-----+--------+---------+-----------+
| StuID | Name          | Age | Gender | ClassID | TeacherID |
+-------+---------------+-----+--------+---------+-----------+
|     1 | Shi Zhongyu   |  22 | M      |       2 |         3 |
|     2 | Shi Potian    |  22 | M      |       1 |         7 |
|     3 | Xie Yanke     |  53 | M      |       2 |        16 |
|     4 | Ding Dian     |  32 | M      |       4 |         4 |
|     5 | Yu Yutong     |  26 | M      |       3 |         1 |
|     6 | Shi Qing      |  46 | M      |       5 |      NULL |
|    11 | Yuan Chengzhi |  23 | M      |       6 |      NULL |
|    13 | Tian Boguang  |  33 | M      |       2 |      NULL |
|    15 | Duan Yu       |  19 | M      |       4 |      NULL |
|    16 | Xu Zhu        |  21 | M      |       1 |      NULL |
|    17 | Lin Chong     |  25 | M      |       4 |      NULL |
|    18 | Hua Rong      |  23 | M      |       7 |      NULL |
|    23 | Ma Chao       |  23 | M      |       4 |      NULL |
|    24 | Xu Xian       |  27 | M      |    NULL |      NULL |
|    25 | Sun Dasheng   | 100 | M      |    NULL |      NULL |
+-------+---------------+-----+--------+---------+-----------+
15 rows in set (0.00 sec)

保存到/tmp/下

:MariaDB [hellodb]> SELECT * FROM students WHERE Gender='M' INTO OUTFILE '/tmp/M.txt';
Query OK, 15 rows affected (0.01 sec)

使用cat可看到如下结果

[root@mysql-master mysql]# cat  /tmp/M.txt 
1   Shi Zhongyu 22  M   2   3
2   Shi Potian  22  M   1   7
3   Xie Yanke   53  M   2   16
4   Ding Dian   32  M   4   4
5   Yu Yutong   26  M   3   1
6   Shi Qing    46  M   5   \N
11  Yuan Chengzhi   23  M   6   \N
13  Tian Boguang    33  M   2   \N
15  Duan Yu 19  M   4   \N
16  Xu Zhu  21  M   1   \N
17  Lin Chong   25  M   4   \N
18  Hua Rong    23  M   7   \N
23  Ma Chao 23  M   4   \N
24  Xu Xian 27  M   \N  \N
25  Sun Dasheng 100 M   \N  \N

仿照 students表结构,创建一个表叫做Ms,然后导入/tmp/M.txt
例:

MariaDB [hellodb]> SELECT * FROM students WHERE Gender='M' INTO OUTFILE '/tmp/M.txt';
Query OK, 15 rows affected (0.01 sec)

例:

MariaDB [hellodb]> CREATE TABLE Ms LIKE students;
Query OK, 0 rows affected (0.03 sec)

例:

MariaDB [hellodb]> DESC Ms;
+-----------+---------------------+------+-----+---------+----------------+
| Field     | Type                | Null | Key | Default | Extra          |
+-----------+---------------------+------+-----+---------+----------------+
| StuID     | int(10) unsigned    | NO   | PRI | NULL    | auto_increment |
| Name      | varchar(50)         | NO   |     | NULL    |                |
| Age       | tinyint(3) unsigned | NO   |     | NULL    |                |
| Gender    | enum('F','M')       | NO   |     | NULL    |                |
| ClassID   | tinyint(3) unsigned | YES  |     | NULL    |                |
| TeacherID | int(10) unsigned    | YES  |     | NULL    |                |
+-----------+---------------------+------+-----+---------+----------------+
6 rows in set (0.02 sec)

导入:
导入:

MariaDB [hellodb]> LOAD DATA INFILE '/tmp/M.txt' INTO TABLE Ms;
Query OK, 15 rows affected (0.00 sec)                
Records: 15  Deleted: 0  Skipped: 0  Warnings: 0

导入完成后查看:

MariaDB [hellodb]> SELECT * FROM Ms;
+-------+---------------+-----+--------+---------+-----------+
| StuID | Name          | Age | Gender | ClassID | TeacherID |
+-------+---------------+-----+--------+---------+-----------+
|     1 | Shi Zhongyu   |  22 | M      |       2 |         3 |
|     2 | Shi Potian    |  22 | M      |       1 |         7 |
|     3 | Xie Yanke     |  53 | M      |       2 |        16 |
|     4 | Ding Dian     |  32 | M      |       4 |         4 |
|     5 | Yu Yutong     |  26 | M      |       3 |         1 |
|     6 | Shi Qing      |  46 | M      |       5 |      NULL |
|    11 | Yuan Chengzhi |  23 | M      |       6 |      NULL |
|    13 | Tian Boguang  |  33 | M      |       2 |      NULL |
|    15 | Duan Yu       |  19 | M      |       4 |      NULL |
|    16 | Xu Zhu        |  21 | M      |       1 |      NULL |
|    17 | Lin Chong     |  25 | M      |       4 |      NULL |
|    18 | Hua Rong      |  23 | M      |       7 |      NULL |
|    23 | Ma Chao       |  23 | M      |       4 |      NULL |
|    24 | Xu Xian       |  27 | M      |    NULL |      NULL |
|    25 | Sun Dasheng   | 100 | M      |    NULL |      NULL |
+-------+---------------+-----+--------+---------+-----------+
15 rows in set (0.00 sec)

MariaDB [hellodb]> 

这样的备份比较节约空间,但是更适用于备份字段和行!

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日期: 2016-01-28分类: Mariadb

标签: mariadb

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