What determines (how to configure) what format string is used by php PDO driver for values of date and timestamp fields?

Question

I have Firebird 3.0 database which have date and timestamp fields and I am using interbase extension (yes - still interbase) and Yii2 framwork in PHP 7.x. And I have Yii code:

Answer 1

If you are looking to confgure globally the format in Yii2, there are a few localized settings in your common config you should set:

Config Example

'timeZone' => 'America/New_York', // Default PHP date in Eastern.
//... other config stuff
'components' => [
    'formatter' => [
        'dateFormat' => 'php:Y-m-d',
        'datetimeFormat' => 'php:Y-m-d H:i:s',
        'decimalSeparator' => '.',
        'thousandSeparator' => ',',
        'defaultTimeZone' => 'UTC',       // DB Source is stored as UTC timezone.
        'timeZone' => 'America/New_York', // When formatter is used, convert to this timezone.
    ],
    //... other config stuff
  ]

Time Checks

Localized timezones can be a pain to manage, so create a page so you better understand localized formatting. See Yii2 Internationalization Docs

<?php
$now = (new \yii\db\Query)->select('NOW()')->scalar(Yii::$app->db);
?>
<table class="table">
    <tr>
        <th>PHP UTC dateTime (+4 Hours):</th>
        <td><?= gmdate('Y-m-d H:i:s')?></td>
    </tr>
    <tr>
        <th>PHP local dateTime:</th>
        <td><?= date('Y-m-d H:i:s')?></td>
    </tr>
    <tr>
        <th>PHP local timeZone:</th>
        <td><?= date_default_timezone_get() ?></td>
    </tr>
    <tr>
        <th>Database Time Raw (expected UTC):</th>
        <td><?= $now ?></td>
    </tr>
    <tr>
        <th>Formatter -> UTC to local dateTime:</th>
        <td><?= Yii::$app->formatter->asDatetime(gmdate('Y-d-m H:i:s')) ?></td>
    </tr>
    <tr>
        <th>Formatter -> realtiveTime from UTC:</th>
        <td><?= Yii::$app->formatter->asRelativeTime(gmdate('Y-m-d H:i:s')) ?></td>
    </tr>
</table>