Specifications

| customers |

| order_items |

| orders |

+-----------------+

5 rows in set (0.06 sec)

You can also use show to see a list of databases by typing

mysql> show databases;

You can see more information about a particular table, for example, books, using DESCRIBE:

mysql> describe books;

MySQL will display the information you supplied when creating the database:

+--------+------------+------+-----+---------+-------+

+--------+------------+------+-----+---------+-------+

+--------+------------+------+-----+---------+-------+

4 rows in set (0.05 sec)

These commands are useful to remind yourself of a column type, or to navigate a database that

you didn’t create.

MySQL Identifiers

There are four kinds of identifiers in MySQL—databases, tables, and columns, which we’re

familiar with, and aliases, which we’ll cover in the next chapter.

Databases in MySQL map to directories in the underlying file structure, and tables map to

files. This has a direct effect on the names you can give them. It also affects the case sensitivity

of these names—if directory and filenames are case sensitive in your operating system, data-

base and table names will be case sensitive (for example, in UNIX), otherwise they won’t (for

example, under Windows). Column names and alias names are not case sensitive, but you can’t

use versions of different cases in the same SQL statement.

As a side note, the location of the directory and files containing the data will be wherever it

was set in configuration. You can check the location on your system by using the mysqladmin

facility as follows:

mysqladmin variables

Creating Your Web Database

HAPTER 8

CREATING YOUR

WEB DATABASE

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