This is my first php program!

PEAR DB Basics
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the database, and more. The components of a DSN are assembled into a URL-like
string:
type(dbsyntax)
://
username
:
password
@
protocol
+
hostspec
/
database
The only mandatory field is
type
, which specifies the PHP database backend to use.
Table 8-1 lists the implemented database types at the time of writing.
Figure 8-1. The movie page
Table 8-1. PHP database types
Name
Database
Mysql
MySQL
Pgsql
PostgreSQL
Ibase
InterBase
Msql
Mini SQL
Mssql
Microsoft SQL Server
oci8
Oracle 7/8/8
i
Odbc
ODBC
Sybase
SyBase
Ifx
Informix
Fbsql
FrontBase
,ch08.16110 Page 193 Wednesday, March 13, 2002 11:44 AM

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This is the Title of the Book, eMatter Edition
Copyright © 2002 O’Reilly & Associates, Inc. All rights reserved.
194
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Chapter 8: Databases
The
protocol
is the communication protocol to use. The two common values are
"tcp"
and
"unix"
, corresponding to Internet and Unix domain sockets. Not every
database backend supports every communications protocol.
These are some sample valid data source names:
mysql:///webdb
mysql://localhost/webdb
mysql://bondview@localhost/webdb
mysql://bondview@tcp+localhost/webdb
mysql://bondview:007@localhost/webdb
In Example 8-1, we connected to the MySQL database
webdb
with the username
bondview
and password
007
.
A common development technique is to store the DSN in a PHP file and include that
file in every page that requires database connectivity. Doing this means that if the
information changes, you don’t have to change every page. In a more sophisticated
settings file, you might even switch DSNs based on whether the application is run-
ning in development or deployment mode.
Connecting
Once you have a DSN, create a connection to the database using the
connect( )
method. This returns a database object you’ll use for tasks such as issuing queries
and quoting parameters:
$db = DB::connect(
DSN
[,
options
]);
The
options
value can either be Boolean, indicating whether or not the connection is to
be persistent, or an array of options settings. The
options
values are given in Table 8-2.
By default, the connection is not persistent and no debugging information is dis-
played. Permitted values for
optimize
are
'performance'
and
'portability'
. The
default is
'performance'
. Here’s how to enable debugging and optimize for portability:
$db = DB::connect($dsn, array('debug' => 1, 'optimize' => 'portability'));
Error Checking
PEAR DB methods return
DB_ERROR
if an error occurs. You can check for this with
DB::isError( )
:
Table 8-2. Connection options