.. _important-1785882500:

============================================
Important: Four job columns are nullable now
============================================

Description
===========

Four columns of :sql:`tx_academicjobs_domain_model_job` were declared as
:sql:`TEXT` with a default value:

..  code-block:: sql

    company_name text NOT NULL DEFAULT '',
    sector text NOT NULL DEFAULT '',
    required_degree text NOT NULL DEFAULT '',
    contractual_relationship text NOT NULL DEFAULT '',

MySQL cannot store a literal default value on a :sql:`TEXT` column. TYPO3 v13
works around that by expressing the default in the :sql:`DEFAULT ('')` syntax
MySQL 8.0.13 introduced. TYPO3 v12 does not. There the columns were created
:sql:`NOT NULL` with no default at all, and every statement that did not name
them was rejected:

..  code-block:: text

    Field 'company_name' doesn't have a default value

Imports and data sets are the reachable case. The frontend form and the
backend are not affected: the form persists a full record, and the
backend fills the columns from their :php:`default` in TCA.

The columns keep their type, lose the default and accept :sql:`NULL`:

..  code-block:: sql

    company_name text DEFAULT NULL,
    sector text DEFAULT NULL,
    required_degree text DEFAULT NULL,
    contractual_relationship text DEFAULT NULL,

Impact
======

Job records can be written on TYPO3 v12 with MySQL without naming these
four columns.

Records written that way now store :sql:`NULL` where they previously
stored an empty string. Existing rows are not changed, so a column can
hold both. The domain model is unaffected, Extbase casts :sql:`NULL` to
an empty string for its :php:`string` properties. Code reading the
columns directly should compare with :php:`empty()` rather than with
:php:`''`.

Affected Installations
======================

All installations of this extension. The database schema has to be
updated, either in :guilabel:`Admin Tools > Maintenance > Analyze Database
Structure` or with :bash:`vendor/bin/typo3 extension:setup`. The change only
relaxes the columns, so no data is converted and nothing can be lost.

.. index:: Database, ext:academic_jobs