Introduction to Database Administrations

by K. Yue

1. Introduction

2. System Catalog

Example:

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sakila             |
| test               |
| world              |
| yue_exp            |
+--------------------+
7 rows in set (0.00 sec)

MySQL database

Example:

Try to add a new user by inserting into the user table: http://dev.mysql.com/doc/refman/5.6/en/adding-users.html. There are problems.

use mysql;

Try:

INSERT INTO user (Host,User,Password,select_priv, insert_priv,     update_priv,ssl_cipher,x509_issuer,x509_subject)
VALUES ('localhost', 'abcde', PASSWORD('IloveDBMS'), 'Y', 'Y', 'Y', 'NULL', 'NULL', 'NULL');

FLUSH PRIVILEGES;

information_schema database

Example:

mysql> SELECT table_name, table_type, row_format, table_rows, avg_row_length
    -> FROM information_schema.tables
    -> WHERE table_schema = 'information_schema'
    -> ORDER BY table_name DESC;
+---------------------------------------+-------------+------------+------------+----------------+
| table_name                            | table_type  | row_format | table_rows | avg_row_length |
+---------------------------------------+-------------+------------+------------+----------------+
| VIEWS                                 | SYSTEM VIEW | Dynamic    |       NULL |              0 |
| USER_PRIVILEGES                       | SYSTEM VIEW | Fixed      |       NULL |           1986 |
| TRIGGERS                              | SYSTEM VIEW | Dynamic    |       NULL |              0 |
| TABLE_PRIVILEGES                      | SYSTEM VIEW | Fixed      |       NULL |           2372 |
| TABLE_CONSTRAINTS                     | SYSTEM VIEW | Fixed      |       NULL |           2504 |
| TABLESPACES                           | SYSTEM VIEW | Fixed      |       NULL |           6951 |
| TABLES                                | SYSTEM VIEW | Fixed      |       NULL |           9450 |
| STATISTICS                            | SYSTEM VIEW | Fixed      |       NULL |           5753 |
| SESSION_VARIABLES                     | SYSTEM VIEW | Fixed      |       NULL |           3268 |
| SESSION_STATUS                        | SYSTEM VIEW | Fixed      |       NULL |           3268 |
| SCHEMA_PRIVILEGES                     | SYSTEM VIEW | Fixed      |       NULL |           2179 |
| SCHEMATA                              | SYSTEM VIEW | Fixed      |       NULL |           3464 |
| ROUTINES                              | SYSTEM VIEW | Dynamic    |       NULL |              0 |
| REFERENTIAL_CONSTRAINTS               | SYSTEM VIEW | Fixed      |       NULL |           4814 |
| PROFILING                             | SYSTEM VIEW | Fixed      |       NULL |            308 |
| PROCESSLIST                           | SYSTEM VIEW | Dynamic    |       NULL |              0 |
| PLUGINS                               | SYSTEM VIEW | Dynamic    |       NULL |              0 |
| PARTITIONS                            | SYSTEM VIEW | Dynamic    |       NULL |              0 |
| PARAMETERS                            | SYSTEM VIEW | Dynamic    |       NULL |              0 |
| KEY_COLUMN_USAGE                      | SYSTEM VIEW | Fixed      |       NULL |           4637 |
| INNODB_TRX                            | SYSTEM VIEW | Fixed      |       NULL |           4534 |
| INNODB_LOCK_WAITS                     | SYSTEM VIEW | Fixed      |       NULL |            599 |
| INNODB_LOCKS                          | SYSTEM VIEW | Fixed      |       NULL |          31244 |
| INNODB_CMP_RESET                      | SYSTEM VIEW | Fixed      |       NULL |             25 |
| INNODB_CMPMEM_RESET                   | SYSTEM VIEW | Fixed      |       NULL |             29 |
| INNODB_CMPMEM                         | SYSTEM VIEW | Fixed      |       NULL |             29 |
| INNODB_CMP                            | SYSTEM VIEW | Fixed      |       NULL |             25 |
| GLOBAL_VARIABLES                      | SYSTEM VIEW | Fixed      |       NULL |           3268 |
| GLOBAL_STATUS                         | SYSTEM VIEW | Fixed      |       NULL |           3268 |
| FILES                                 | SYSTEM VIEW | Fixed      |       NULL |           2677 |
| EVENTS                                | SYSTEM VIEW | Dynamic    |       NULL |              0 |
| ENGINES                               | SYSTEM VIEW | Fixed      |       NULL |            490 |
| COLUMN_PRIVILEGES                     | SYSTEM VIEW | Fixed      |       NULL |           2565 |
| COLUMNS                               | SYSTEM VIEW | Dynamic    |       NULL |              0 |
| COLLATION_CHARACTER_SET_APPLICABILITY | SYSTEM VIEW | Fixed      |       NULL |            195 |
| COLLATIONS                            | SYSTEM VIEW | Fixed      |       NULL |            231 |
| CHARACTER_SETS                        | SYSTEM VIEW | Fixed      |       NULL |            384 |
+---------------------------------------+-------------+------------+------------+----------------+
37 rows in set (0.08 sec)

 

performance_schema database

Example:

-- Number of schema with no table.
select count(*)
from information_schema.schemata s
   left join information_schema.tables t on s.schema_name = t.table_schema
where t.table_name is null;

-- Show user account including some privilege information
select host, user, create_user_priv, show_db_priv
from user;

Notes:

Tools

HeidiSQL:

Hedi1

Classroom example follows.

PHPMyAdmin:

phpMyAdmin

To PHPMyAdmin:

Classroom example follows.