PHP three ways to connect to MySQL database (MySQL, mysqli, PDO)

PHP and MySQL connection has three kinds of API interface, namely: PHP mysql extension, php mysqli extension, PHP data Object (PDO), below for the above three kinds of connection methods to do a summary, in order to choose the best solution under different scenarios.

PHP's MySQL extension is a design development that allows PHP applications to interact with the MySQL database in an early extension. The MySQL extension provides a process-oriented interface and is designed for MySQL4.1.3 or earlier versions. This extension, though, can interact with the MySQL4.1.3 or newer database server, but does not support some of the features provided by the late MySQL server. Because it is too old and unsafe, it has been completely replaced by the later mysqli.

PHP's mysqli extension, which we sometimes call MySQL enhanced extension, can be used for new advanced features in MySQL4.1.3 or later versions. Its features are: Object-oriented interface, prepared statement support, multi-statement execution support, transaction support, enhanced debugging ability, embedded service support, preprocessing method completely solves the problem of SQL injection. However, it also has the disadvantage of only supporting MySQL database. This is certainly the best option if you don't operate other databases.

PDO is the abbreviation for PHP Data objects and is a Database abstraction layer specification in PHP applications. PDO provides a unified API interface that allows your PHP application to not care about the type of database server system you want to connect to, that is, if you use the PDO API, you can seamlessly switch database servers whenever you need them, such as from Oracle to MySQL, Just need to modify very little PHP code. It functions similar to interfaces such as JDBC, ODBC, DBI, and so on. Similarly, it solves the SQL injection problem and has good security. However, he also has shortcomings, some multi-statement execution query is not supported (but this situation is very small).

Frustration has also made a list of comparisons between the three of them:

	PHP mysqli Extensions	Pdo	MySQL Extension for PHP
Introduction of PHP Version	5.0	5.0	3.0 ago
Does the php5.x contain	Is	Is	Is
MySQL Development status	Active	Active in the PHP5.3	Maintenance only
Recommended use in MySQL new project	Recommendation-Preferred	Suggestions	Not recommended
Character set support for the API	Is	Is	Whether
Support for server-side prepare statements	Is	Is	Whether
Support for client Prepare statements	Whether	Is	Whether
Stored Procedure Support Scenarios	Is	Is	Whether
Multi-statement execution support scenarios	Is	Most	Whether
Do you support all MySQL4.1 features above	Is	Most	Whether

Judging from the official results, MSQLI is preferred, followed by PDO. Many of the results given by the "folk" are inclined to use PDO because they are not burdened with the advantages of cross-Library, but also have the characteristics of fast reading and writing speed.

1.PHP with MySQL extension (this extension has been deprecated since PHP 5.5.0, and will be removed in the future), the PHP native way to connect to the database is process-oriented

<?php
$mysql _conf = Array (
' Host ' = ' 127.0.0.1:3306 ',
' db ' = ' Test ',
' Db_user ' = ' root ',
' Db_pwd ' = ' root ',
);
$mysql _conn = @mysql_connect ($mysql _conf[' host '], $mysql _conf[' Db_user '), $mysql _conf[' db_pwd ']);
if (! $mysql _conn) {
Die ("Could does connect to the database:\n". Mysql_error ());//Diagnostic connection Error
}
mysql_query ("Set names ' UTF8 '");//Code conversion
$select _db = mysql_select_db ($mysql _conf[' db ');
if (! $select _db) {
Die ("Could does connect to the db:\n". Mysql_error ());
}
$sql = "SELECT * from user;";
$res = mysql_query ($sql);
if (! $res) {
Die ("could get the res:\n". Mysql_error ());
}

while ($row = Mysql_fetch_assoc ($res)) {
Print_r ($row);
}

Mysql_close ($mysql _conn);
?>

2.PHP and mysqli extension, process-oriented, object

<?php
$mysql _conf = Array (
' Host ' = ' 127.0.0.1:3306 ',
' db ' = ' Test ',
' Db_user ' = ' root ',
' Db_pwd ' = ' joshua317 ',
);

$mysqli = @new mysqli ($mysql _conf[' host '], $mysql _conf[' Db_user '), $mysql _conf[' db_pwd ']);
if ($mysqli->connect_errno) {
Die ("Could does connect to the database:\n". $mysqli->connect_error);//Diagnostics Connection Error
}
$mysqli->query ("Set names ' UTF8 ';"); /Code Conversion
$select _db = $mysqli->select_db ($mysql _conf[' db ']);
if (! $select _db) {
Die ("Could does connect to the db:\n". $mysqli->error);
} $sql = "Select uid from user where name = ' Joshua ';";
$res = $mysqli->query ($sql);
if (! $res) {
Die ("SQL error:\n". $mysqli->error);
}
while ($row = $res->fetch_assoc ()) {
Var_dump ($row);
}

$res->free ();
$mysqli->close ();
?>

2.PHP and PDO extensions, process-oriented, object

<?php
$mysql _conf = Array (
' Host ' = ' 127.0.0.1:3306 ',
' db ' = ' Test ',
' Db_user ' = ' root ',
' Db_pwd ' = ' joshua317 ',
);
$pdo = new PDO ("mysql:host=". $mysql _conf[' host '). ";d bname=". $mysql _conf[' db '], $mysql _conf[' Db_user '), $mysql _conf[' db_pwd ']);//Create a PDO object
$pdo->exec ("Set names ' UTF8 '");
$sql = "SELECT * from user where name =?";
$stmt = $pdo->prepare ($sql);
$stmt->bindvalue (1, ' Joshua ', PDO::P aram_str);
$rs = $stmt->execute ();
if ($rs) {
Pdo::fetch_assoc Associative Array Form
Pdo::fetch_num Numeric index Array form
while ($row = $stmt->fetch (PDO::FETCH_ASSOC)) {
Var_dump ($row);
}
}

$pdo = null;//Close Connection
?>

PHP three ways to connect to MySQL database (MySQL, mysqli, PDO)