MySQL Cookbook

Conventions Used in This Book

The following font conventions have been used throughout the book:

Constant width

Used for program listings, as well as within paragraphs to refer to program elements such as variable or function names.

Constant width bold

Used to indicate text that you type when running commands.

Constant width italic

Used to indicate variable input; you should substitute a value of your own choosing.

Italic

Used for URLs, hostnames, names of directories and files, Unix commands and options, and occasionally for emphasis.

Commands often are shown with a prompt to illustrate the context in which they are used. Commands that you issue from the command line are shown with a % prompt:

% chmod 600 my.cnf

That prompt is one that Unix users are used to seeing, but it doesn't necessarily signify that a command will work only under Unix. Unless indicated otherwise, commands shown with a % prompt generally should work under Windows, too.

If you should run a command under Unix as the root user, the prompt is # instead:

# chkconfig --add tomcat4

For commands that are specific only to Windows, the C:\> prompt is used:

C:\> copy C:\mysql\lib\cygwinb19.dll C:\Windows\System

SQL statements that are issued from within the mysql client program are shown with a mysql> prompt and terminated with a semicolon:

mysql> SELECT * FROM my_table;

For examples that show a query result as you would see it when using mysql, I sometimes truncate the output, using an ellipsis (...) to indicate that the result consists of more rows than are shown. The following query produces many rows of output, of which those in the middle have been omitted:

mysql> SELECT name, abbrev FROM states ORDER BY name;
+----------------+--------+
| name           | abbrev |
+----------------+--------+
| Alabama        | AL     |
| Alaska         | AK     |
| Arizona        | AZ     |
...
| West Virginia  | WV     |
| Wisconsin      | WI     |
| Wyoming        | WY     |
+----------------+--------+

Examples that just show the syntax for SQL statements do not include the mysql> prompt, but they do include semicolons as necessary to make it clear where statements end. For example, this is a single statement:

CREATE TABLE t1 (i INT)
SELECT * FROM t2;

But this example represents two statements:

CREATE TABLE t1 (i INT);
SELECT * FROM t2;

The semicolon is a notational convenience used within mysql as a statement terminator. But it is not part of SQL itself, so when you issue SQL statements from within programs that you write (for example, using Perl or Java), you should not include terminating semicolons.

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