資料，資料，命根就在資料 ! 操作資料庫時，一定要謹慎小心。師萬物 這裡的程式碼看看就好，要有自己的判斷。遇到抉擇，要不恥上下問。

example

stu@Ubuntu:~$ mysql -u root -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 16
Server version: 8.0.12 MySQL Community Server - GPL

Copyright (c) 2000, 2018, Oracle and/or
 
 its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> show databases;
+--------------------+
 

| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
+--------------------+
4 rows in set (0.00 sec)

mysql> use information_schema;
Reading table information for completion of table and column names
You can turn off
 
 this feature to get a quicker startup with -A

Database changed
mysql> show tables;
+---------------------------------------+
| Tables_in_information_schema          |
+---------------------------------------+
| CHARACTER_SETS                        |
| COLLATIONS                            |
| COLLATION_CHARACTER_SET_APPLICABILITY |
| COLUMNS                               |
| COLUMN_PRIVILEGES                     |
| COLUMN_STATISTICS                     |
| ENGINES                               |
| EVENTS                                |
| FILES                                 |
| INNODB_BUFFER_PAGE                    |
| INNODB_BUFFER_PAGE_LRU                |
| INNODB_BUFFER_POOL_STATS              |
| INNODB_CACHED_INDEXES                 |
| INNODB_CMP                            |
| INNODB_CMPMEM                         |
| INNODB_CMPMEM_RESET                   |
| INNODB_CMP_PER_INDEX                  |
| INNODB_CMP_PER_INDEX_RESET            |
| INNODB_CMP_RESET                      |
| INNODB_COLUMNS                        |
| INNODB_DATAFILES                      |
| INNODB_FIELDS                         |
| INNODB_FOREIGN                        |
| INNODB_FOREIGN_COLS                   |
| INNODB_FT_BEING_DELETED               |
| INNODB_FT_CONFIG                      |
| INNODB_FT_DEFAULT_STOPWORD            |
| INNODB_FT_DELETED                     |
| INNODB_FT_INDEX_CACHE                 |
| INNODB_FT_INDEX_TABLE                 |
| INNODB_INDEXES                        |
| INNODB_METRICS                        |
| INNODB_TABLES                         |
| INNODB_TABLESPACES                    |
| INNODB_TABLESPACES_BRIEF              |
| INNODB_TABLESTATS                     |
| INNODB_TEMP_TABLE_INFO                |
| INNODB_TRX                            |
| INNODB_VIRTUAL                        |
| KEYWORDS                              |
| KEY_COLUMN_USAGE                      |
| OPTIMIZER_TRACE                       |
| PARAMETERS                            |
| PARTITIONS                            |
| PLUGINS                               |
| PROCESSLIST                           |
| PROFILING                             |
| REFERENTIAL_CONSTRAINTS               |
| RESOURCE_GROUPS                       |
| ROUTINES                              |
| SCHEMATA                              |
| SCHEMA_PRIVILEGES                     |
| STATISTICS                            |
| ST_GEOMETRY_COLUMNS                   |
| ST_SPATIAL_REFERENCE_SYSTEMS          |
| TABLES                                |
| TABLESPACES                           |
| TABLE_CONSTRAINTS                     |
| TABLE_PRIVILEGES                      |
| TRIGGERS                              |
| USER_PRIVILEGES                       |
| VIEWS                                 |
+---------------------------------------+
62 rows in set (0.00 sec)

mysql> describe CHARACTER_SETS;
+----------------------+------------------+------+-----+---------+-------+
| Field                | Type             | Null | Key | Default | Extra |
+----------------------+------------------+------+-----+---------+-------+
| CHARACTER_SET_NAME   | varchar(64)      | NO   |     | NULL    |       |
| DEFAULT_COLLATE_NAME | varchar(64)      | NO   |     | NULL    |       |
| DESCRIPTION          | varchar(2048)    | NO   |     | NULL    |       |
| MAXLEN               | int(10) unsigned | NO   |     | NULL    |       |
+----------------------+------------------+------+-----+---------+-------+
4 rows in set (0.01 sec)

mysql> exit;
Bye
stu@Ubuntu:~$ 

resource

MySQL是一個關係型資料庫管理系統，目前是開源的(2018-10)。 許可權明確，恰當選擇引擎與字符集，命名簡潔明瞭與規範。 MariaDB，Redis，MongoDB，PostgreSQL，Hive，HBase等，可以簡單地瞭解。 Workbench，phpMyAdmin，Navicat等圖形化管理工具，可以試用一下。