PHP PEAR: MDB2

The PEAR DB class has been deprecated and replaced with MDB2.

MDB2 doesn't come with the MySQL driver out to the box, so you need to install that separately:

$ pear install MDB2
$ pear install MDB2_Driver_mysql

Here's a simple select, using the default fetchmode of MDB2_FETCHMODE_ORDERED.

<?
require_once "MDB2.php";

$dsn = 'mysql://my_username:@my_password@127.0.0.1/my_db';

$options = array(
    'debug' => 2,
    'result_buffering' => false,
);

$mdb2 =& MDB2::factory($dsn, $options);
if (PEAR::isError($mdb2)) {
    die($mdb2->getMessage());
}

// Proceed with a query...
$res =& $mdb2->query('SELECT * FROM my_table');

// Always check that result is not an error
if (PEAR::isError($res)) {
    die($res->getMessage());
}

// Iterate through result set (assume default fetchmod is MDB2_FETCHMODE_ORDERED)
while (($row = $res->fetchRow())) {
    echo $row[0] . " " . $row[1] . "<br/>\n";
}

?>

The three possible fetchmode values are:
1) MDB2_FETCHMODE_ORDERED (query results returned as array - column numbers are keys)
2) MDB2_FETCHMODE_ASSOC (query results returned as hash/associative array - column names are keys)
3) MDB2_FETCHMODE_OBJECT (query results returned as object - column names as properties)


To change the default fetchmode and use MDB2_FETCHMODE_ASSOC instead, use the setFetchMode method:

$mdb2->setFetchMode(MDB2_FETCHMODE_ASSOC);

and then iterate through the results:

while ($row = $res->fetchRow()) {
    echo $row['column_name_a'] . ' ' . $row['column_name_b'] . "<br/>\n";
}

Or you can change it per call:

while ($row = $res->fetchRow(MDB2_FETCHMODE_ASSOC)) {
    echo $row['client_abbrv'] . ' ' . $row['client_name'] . "<br/>\n";
}

Here's an example of the first method:

<?
require_once "MDB2.php";

$dsn = 'mysql://my_username:@my_password@127.0.0.1/my_db';

$options = array(
    'debug' => 2,
    'result_buffering' => false,
);

$mdb2 =& MDB2::factory($dsn, $options);
if (PEAR::isError($mdb2)) {
    die($mdb2->getMessage());
}

// Set the fetchmode
$mdb2->setFetchMode(MDB2_FETCHMODE_ASSOC);

// Proceed with a query...
$res =& $mdb2->query('SELECT * FROM my_table');

// Always check that result is not an error
if (PEAR::isError($res)) {
    die($res->getMessage());
}

// Iterate through result set
while ($row = $res->fetchRow()) {
    echo $row['column_name_a'] . ' ' . $row['column_name_b'] . "<br/>\n";
}

?>

You can insert data with a prepared statement:

<?
require_once "MDB2.php";

$dsn = 'mysql://my_username:@my_password@127.0.0.1/my_db';

$options = array(
    'debug' => 2,
    'result_buffering' => false,
);

$mdb2 =& MDB2::factory($dsn, $options);
if (PEAR::isError($mdb2)) {
    die($mdb2->getMessage());
}

// Insert
$statement = $mdb2->prepare('INSERT INTO clients VALUES (?, ?)');
$data = array($var1, $var2);
$statement->execute($data);
$statement->free();
?>

These are just the basics...read all the goodness here:

http://pear.php.net/manual/en/package.database.mdb2.php

PHP PEAR: MDB2 Error: connect failed (localhost MySQL)

I ran into a persistent connect error when trying to connect to localhost MySQL database with MDB2.

Instead of:

dsn: mysql://my_username:my_password@localhost/my_db

use:

dsn: mysql://my_username:my_password@127.0.0.1/my_db

Viewing Ruby Gem documentation

1) Command line

$ ri <gem_name>

2) Browser (http://localhost:8808)

$ gem_server

Emulate PHP5 str_split() in PHP4

/* emulate the php5 str_split function
* array str_split( string $string [, int $split_length])
* Converts a string to an array
* If the optional split_length param is specified, the returned array
* will be broken down into chunks with each being split_length in
* length, otherwise each chuck will be one character in length.
* False is returned if split_length is less than 1. If the split_length
* length exceeds the length of string, the entire string is returned
* as the first (and only) array element.
*/

If you want to use optional split_length:

function str_split($str, $l=1) {
  $str_array = explode("\r\n", chunk_split($str,$l));
  return $str_array;
}

Or optionally, if you just need the simple split (split_length=1):

function str_split($str) {
  $str_array=array();
  $len=strlen($str);
  for($i=0; $i<$len; $i++) {
    $str_array[]=$str{$i};
  }
  return $str_array;
}

Gem List

Here's a command to list all your installed Gems:

gem list | grep '^[a-zA-Z]'