<?php
 /*
 * From the DB_(driver) objects
 */
 // get the object with, ie:
 $db = DB::connect('mysql://user:pass@localhost/my_db');
 
 // Set options
 $db->setErrorHandling();
 $db->setFetchmode();
 // Information
 $db->affectedRows();
 $db->tableInfo();
 // Database manipulation
 $db->query();
 // Data fetch
 $db->nextId();
 $db->getOne();
 $db->getRow();
 $db->getCol();
 $db->getAssoc();
 $db->getAll();
 // Place holders and execute related
 $db->quote();
 $db->prepare();
 $db->execute();
 $db->executeMultiple();
 // Transactions
 $db->autoCommit();
 $db->commit();
 $db->rollback();
 // Disconnection
 $db->disconnect();
 
 /*
 * From DB_result objects
 */
 // get the object with, ie: 
 $res = $db->query('select * from foo');
 
 // Data fetch
 $res->fetchRow();
 $res->fetchInto();
 // Result Info
 $res->numCols();
 $res->numRows();
 $res->tableInfo();
 // Free
 $res->free();
 
 /*
 * From DB_error objects
 */
 // get the object with, ie:
 $error = $db->query('select * from no_table');
 
 $error->getMessage();
 $error->getDebugInfo();
 $error->toString();
 ?>

<?php
 ...
 $res = $db->query('select * from no_table');
 if (DB::isError($res)) {
     // get the portable error string
     echo $res->getMessage();
 }
 ?>

<?php
 $sql = 'select * from no_table';
 if (DB::isError($res = $db->query($sql))) {
     // get the native backend error
     // and the last query
     echo $res->getDebugInfo();
 }
 ?>

<?php
 // what messages to report
 error_reporting (E_ALL ^ E_NOTICE);
 // this function will handle all reported errors
 function my_error_handler ($errno, $errstr, $errfile, $errline) {
     echo "In $errfile, line: $errline\n
$errstr";
 }
 set_error_handler ('my_error_handler');
 $db = DB::connect('pgsql://postgres@localhost/no_db');
 ...
 ?>

<?php
 require_once 'DB.php';
 // Set the default action to take on error
 PEAR::setErrorHandling(PEAR_ERROR_DIE);
 // From here you don't need to check errors any more
 $db = DB::connect('pgsql://postgres@localhost/my_database');
 $res = $db->query('select id from no_table');
 // at this point the execution is aborted and the error message is raisen
 ...
 ?>

<?php
 // Define the app environment (this is: what errors you want to output)
 define ('DEBUG_ENV', true);
 // This function will handle all errors
 function handle_pear_error ($error_obj) {
     // Be verbose while developing the application
     if (DEBUG_ENV) {
         die ($error_obj->getMessage()."\n".$error_obj->getDebugInfo());
     // Dump a silly message if the site is in production
     } else {
         die ('Sorry you request can not be processed now. Try again later');
     }
 }
 
 require_once 'DB.php';
 // On error, call the "handle_pear_error" function back
 // You can also use an object as pear error handler so:
 // setErrorHandling(PEAR_ERROR_CALLBACK, array($object,'method_name');
 PEAR::setErrorHandling(PEAR_ERROR_CALLBACK, 'handle_pear_error');
 $db = DB::connect('pgsql://postgres@localhost/site_db');
 $res = $db->query('select id from no_table');
 // at this point the execution is aborted and the "handle_pear_error"
 // function is called with the error object as its first argument
 while ($row = $res->fetchRow()) {
     ...
 }
 ...
 ?>

<?php
 error_reporting (E_ALL ^ E_NOTICE);
 // this function will handle all errors reported by PHP
 function php_error_handler ($errno, $errstr, $errfile, $errline) {
     die ("In $errfile, line: $errline\n
$errstr");
 }
 set_error_handler ('php_error_handler');
 // this function will catch errors generated by Pear,
 // transform it to PHP errors and trigger them to the php_error_handler
 function pear_error_handler ($err_obj) {
     $error_string = $err_obj->getMessage() . '
' . $error_obj->getDebugInfo();
     trigger_error ($error_string, E_USER_ERROR);
 }
 require 'DB.php';
 PEAR::setErrorHandling (PEAR_ERROR_CALLBACK, 'pear_error_handler');
 // force an error
 $db = DB::connect('pgsql://postgres@localhost/no_db');
 ...
 ?>