MySQL Introductory learning (vi)

MySQL MySQL primer learning (vi)
--Modification and backup, batch processing

Sometimes we have to modify and delete database tables and databases, which can be implemented in the following ways:

1. Add one column:
Add a column in the MyTable table in the previous example to indicate whether single singles:
Mysql> ALTER TABLE mytable add column single char (1);

2, modify the record
Modify the Abccs single record to "Y":
mysql> Update mytable set single= ' y ' where name= ' Abccs ';

Now let's see what's going on:
Mysql> select * FROM MyTable;
+----------+------+------------+-----------+--------+
| name | sex | Birth | birthaddr | Single |
+----------+------+------------+-----------+--------+
| Abccs |f | 1977-07-07 | Our | y |
| Mary |f | 1978-12-12 | USA | NULL |
| Tom |m | 1970-09-02 | USA | NULL |
+----------+------+------------+-----------+--------+

3, increase the record
I've already talked about how to add a record to make it easier to see and repeat with this:
mysql> INSERT INTO MyTable
-> VALUES (' abc ', ' F ', ' 1966-08-17 ', ' o ', ' n ');
Query OK, 1 row affected (0.05 sec)
Check this out:
Mysql> select * FROM MyTable;
+----------+------+------------+-----------+--------+
| name | sex | Birth | birthaddr | Single |
+----------+------+------------+-----------+--------+
| Abccs |f | 1977-07-07 | Our | y |
| Mary |f | 1978-12-12 | USA | NULL |
| Tom |m | 1970-09-02 | USA | NULL |
| ABC |f | 1966-08-17 | Our | n |
+----------+------+------------+-----------+--------+


3, delete the record
Delete a record in the table with the following command:
Mysql> Delete from mytable where name= ' abc ';
Delete Deletes a record from the table that satisfies the condition given by the where.

Show the results again:
Mysql> select * FROM MyTable;
+----------+------+------------+-----------+--------+
| name | sex | Birth | birthaddr | Single |
+----------+------+------------+-----------+--------+
| Abccs |f | 1977-07-07 | Our | y |
| Mary |f | 1978-12-12 | USA | NULL |
| Tom |m | 1970-09-02 | USA | NULL |
+----------+------+------------+-----------+--------+

4, delete the table:
mysql> DROP TABLE * * * * * * (table 1 name), * * * Table 2 name;
You can delete one or more tables and use them carefully.

5, the deletion of the database:
mysql> drop database name;
Use caution.

6, the database backup:
Back to Dos:
Mysql> quit
D:mysqlbin
Use the following command to back up the database Abccs:
Mysqldump--opt ABCCS>ABCCS.DBB
ABCCS.DBB is the backup file for your database Abccs.

7. Use MySQL in batch processing mode:

First, create a batch file Mytest.sql, which reads as follows:
Use Abccs;
SELECT * FROM MyTable;
Select Name,sex from mytable where name= ' Abccs ';

Run the following command under DOS:
D:mysqlbin MySQL < Mytest.sql
The execution results are displayed on the screen.

If you want to see the results and have a lot of output, you can use this command:
MySQL < Mytest.sql | More

We can also output the results to a file:
MySQL < mytest.sql > mytest.out