


How to Connect to Multiple MySQL Databases from a Single PHP Webpage?
Dec 20, 2024 pm 08:44 PMConnecting to Multiple MySQL Databases on a Single Webpage
Question:
How can we establish connections to multiple MySQL databases within a single PHP webpage? Currently, we are aware of connecting to a single database using mysql_connect(). However, we want to extend this functionality to multiple databases.
Answer:
Using multiple mysql_connect() commands is possible for connecting to different databases, but it requires specifying true for the fourth parameter ('new_link') to prevent reusing the same connection. For instance:
$dbh1 = mysql_connect($hostname, $username, $password); $dbh2 = mysql_connect($hostname, $username, $password, true);
To select a specific database, pass the corresponding link identifier:
mysql_select_db('database1', $dbh1); mysql_select_db('database2', $dbh2);
Then, use the link identifier when executing queries:
mysql_query('SELECT * FROM tablename', $dbh1); // database1 mysql_query('SELECT * FROM tablename', $dbh2); // database2
Warning: It's important to note that mysql_connect() is deprecated in PHP 7.0 and removed in PHP 7.2. It is recommended to use the newer PDO functions for database connectivity.
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