ADOdb and PDO are both database abstraction libraries for PHP that allow developers to write database-independent code. ADOdb hides database specifics and provides a consistent API, additional functions, and better performance compared to PDO. Both libraries establish database connections using object-oriented methods and execute SQL queries by iterating through result sets. While PDO focuses only on basic data access and prepared statements, ADOdb offers more advanced features like pagination, blob handling, and error handling.

1. PHP: ADOdb or PDO for DB Access Tom Rogers Northwestern University Department of Anesthesiology

2. Definition of Database Access A database abstraction layer is an application programming interface which unifies the communication between a computer application and databases such as PostgreSQL , Oracle or SQLite . (Wikipedia) Database abstraction layers reduce the amount of work by providing a consistent API to the developer and hide the database specifics behind this interface as much as possible. (Wikipedia)

3. DB Access/Abstraction Libraries/Classes Available PHP Native Libraries Mysql, Msqli Pgsql Pear:DB Pear:MDB2 ADOdb PDO

4. ADOdb ADOdb is a database abstraction library for PHP and Python based on the same concept as Microsoft's ActiveX Data Objects . It allows developers to write applications in a fairly consistent way regardless of the underlying database storing the information. The advantage is that the database can be changed without re-writing every call to it in the application. (Wikipedia)

5. PDO PDO provides a data-access abstraction layer, which means that, regardless of which database you're using, you use the same functions to issue queries and fetch data. (PHP Documentation)

6. DB Connections ADOdb: include('/path/to/adodb.inc.php'); $ado = NewADOConnection('mysql'); $ado->Connect($server, $user, $pwd, $database); ADOdb(dsn): Include('/path/to/adodb.inc.php'); $ado = NewADOConnection(“mysql://$user:$pwd@$server/$database”); PDO: As of PHP 5.1 no extensions needed, although db driver has to be enabled $pdo = new PDO('mysql:host=localhost;dbname=database',”$user”,”$pwd”);

7. ADOdb: SQL Query and Iteration $sql = “select pk, description from tbl_demo”; ADOdb: (multi-record dataset) foreach($ado->Execute($sql) as $row){ $pk = $row['pk']; $description = $row['description']; ... process code ... } ADOdb: (single record) $row = $ado->GetRow($sql); $pk = $row['pk']; $description = $row['description'];

8. PDO: SQL Query and Iteration $sql = “select pk, description from tbl_demo”; PDO: foreach($pdo->query($sql) as $row){ $pk = $row['pk']; $description = $row['description']; ... process code ... } As far as I can tell, there is no PDO equivalent to ADOdb's “GetRow” method.

9. Functions Available ADOdb (http://phplens.com/adodb/) Connection Management DB Dictionary Library DB-backed Sessions DB Perform. Monitoring Pagination of Record Sets Blob Handling Transactions String, Date Manipulation Error Handling CSV Export PDO ( http://us2.php.net/pdo ) Connection Management Prepared Statements/Stored Procedures Large Objects (LOB) Transactions Error Handling

10. Benchmarks http://joseph.randomnetworks.com/archives/2006/04/04/php-database-functions-vs-peardb-vs-adodb/