Database error: "Field 'start_date' doesn't have a default value" on Civil 5.47.0

[chrisgaraffa]

Just ran into this with CiviCRM 5.47.0 on WordPress 5.9.1. The site had been migrated from Civi 5.4.0 on Drupal 7.60.

Creating a new membership gives the error:

Mar 14 09:45:36  [error] $Fatal Error Details = Array
(
    [callback] => Array
        (
            [0] => CRM_Core_Error
            [1] => exceptionHandler
        )
 that
    [code] => -1
    [message] => DB Error: unknown error
    [mode] => 16
    [debug_info] => INSERT INTO `civicrm_membership_period` (`contact_id` , `membership_id` , `membership_type_id` ) VALUES ( 200113 ,  24452 ,  1 )  [nativecode=1364 ** Field 'start_date' doesn't have a default value]
    [type] => DB_Error
    [user_info] => INSERT INTO `civicrm_membership_period` (`contact_id` , `membership_id` , `membership_type_id` ) VALUES ( 200113 ,  24452 ,  1 )  [nativecode=1364 ** Field 'start_date' doesn't have a default value]
    [to_string] => [db_error: message="DB Error: unknown error" code=-1 mode=callback callback=CRM_Core_Error::exceptionHandler prefix="" info="INSERT INTO `civicrm_membership_period` (`contact_id` , `membership_id` , `membership_type_id` ) VALUES ( 200113 ,  24452 ,  1 )  [nativecode=1364 ** Field 'start_date' doesn't have a default value]"]
)

The relevant lines from the error log seem to be:

#12 /srv/www/SITE/public_html/wp-content/uploads/civicrm/ext/io.github.iamriajul.membershipperiodtracker/CRM/MembershipPeriodTracker/BAO/MembershipPeriod.php(22): CRM_Core_DAO->save()
#13 /srv/www/SITE/public_html/wp-content/uploads/civicrm/ext/io.github.iamriajul.membershipperiodtracker/membershipperiodtracker.php(164): CRM_MembershipPeriodTracker_BAO_MembershipPeriod::create((Array:6))