


Detailed explanation of PHP script database functions (Part 2)_PHP tutorial
Jul 21, 2016 pm 04:04 PM
Use classes to speed up PHP database development
There are many database access functions, and improper use will reduce efficiency and even lead to errors. PHP itself is open and extensible, and many people develop source code for various functions for it. Every PHP programmer should be good at inheriting the results of others and saving time and energy. Only by standing on the shoulders of giants can we see further. Of course, you can also share your code and experience the sense of accomplishment that comes from having your work recognized and creating value.
Using database classes allows us to completely ignore the specific database type and focus on program development.
Among the many development toolkits, PHPLib is one with more stable performance and more complete functions. PHPLib is available at http://phplib.netuse.de/. It contains database support classes. Taking the MySQL database as an example, PHPLib comes with a class named DB_Sql. It packages functions such as database connection, query, result retrieval, and database table traversal.
Using database classes allows us to completely ignore the specific database type and focus on program development. Even if the database system type is changed, the program code does not need to be changed. At the same time, the database class provides a complete and robust database access method, which may be the biggest advantage of using class packaging.
Next, we will use the database class provided by PHPLib to access the database we just created and display the content. 〈?
//Declare an instance of the database class
$db-〉connect("ResumeDB", "localhost", "root", "");
//Connect to the database server
//The parameters provided are: database name, host name, user name, user password
if ($db-〉Link_ID)
// Determine whether it is correctly established Connection
{
$db-〉query("select ID,Name,Intro FROM Resume");
//Query
if ($ db-〉nf())
// Determine whether the result set is empty
{
while ($db-〉next_record())
//Get the record value of the next row until the record set content is fetched
{
echo "ID:", $db-〉f("ID"); //f() function Return the value of a subsection of the current record
echo "〈br〉";
echo "Name:";
$db-〉p("Name");
// The p() function directly prints the value of a certain subsection
// Equivalent to echo $db-〉f("name")
echo "〈 br〉";
echo "Introduction:";
echo $db-〉f("Intro");
echo "〈br〉";
echo "〈a href= "download.php?ID=".$db-〉f("ID").""〉View Word document〈/a〉";
echo "〈 br〉〈hr〉"; ??
}
}
$db->free ();
// Release resources
}
?〉
As can be seen from the above process, the method of accessing the database using classes is basically the same as the method of directly accessing the database. The difference is that the methods we call here are all class methods, rather than functions specific to a certain database. Due to the separation of code and specific database types, when the database system changes, we do not need to change the program code, we only need to change the implementation method of the base class.
If combined with PHPLib template for design, the separation of program and display can be achieved. It will also make the program structure clear and facilitate web page art design and production.
Simple usage, reasonable task allocation, and thoughtful object packaging will greatly improve the efficiency of website development.
Attachment: Code testing platform
All the above program codes were tested on the following platform and passed
RedHat Linux 6.1+Apache1.3.12+
PHP4.0+MySql3. 22.32
The installation and configuration process of the database is:
cd /usr/local/src/mysql*
./configure --refix=/usr/local/mysql
make
make install
The installation and configuration process of Apache is:
cd /usr/local/src/apache*
. /configure --prefix=/usr/local/apache --enable-shared=max
make
make install
The installation and configuration process of PHP is:
cd /usr/local/src/php*
./configure --with-apxs=/usr/local/apache/bin/apxs
--with-config- file-path=/usr/local/
apache/conf
--with-mysql=/usr/local/mysql
--enable-debug=no
--enable-track-vars
The php.ini configuration process is:
Copy php.ini-dist to /usr/local/
apache /conf/php.ini
Edit httpd.conf and remove the comments from the following two lines
AddType application/x-httpd-php .php .php3
AddType application /x-httpd-php-source .phps
<

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