..  _important-study-plan-credit-points-are-decimal:

=================================================
Important: Study plan credit points take decimals
=================================================

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

The credit points of a study plan semester and of a study plan module accept a
number with up to two decimals now, such as 2.5 for a module worth two and a
half credit points. The backend field used to accept whole numbers only. It
takes a decimal point or a decimal comma, and rounds a third decimal, as every
decimal field of the backend does.

The column :sql:`credit_points` of the tables
:sql:`tx_academicstudyplan_domain_model_semester` and
:sql:`tx_academicstudyplan_domain_model_module` changes from
:sql:`int(11)` to :sql:`decimal(10,2) unsigned`.

The study plan shows credit points without trailing zeros: "2.5" and "30",
never "2.50" or "30.00". The semesters and modules handed to the template carry
the credit points as a number rather than as the value the database returns,
so this holds for template overrides as well: printed as they are, they read
"2.5", "30" and "0".

Impact
======

The database compare offers a change of the column in both tables. It keeps
every stored value: a module with 5 credit points keeps them, and the study
plan shows "5" as before. Run it before editors enter a decimal value, which
the integer column cannot hold on MariaDB, MySQL and PostgreSQL.

A semester or module without credit points still shows none.

Credit points render with a decimal point on every page language. A template
override that wants a decimal comma formats the number itself, for example
with :html:`<f:format.number decimalSeparator=",">`, which prints a fixed
number of decimals.

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

Every installation with the extension installed. Run the database
compare in :guilabel:`Admin Tools > Maintenance > Analyze Database Structure`,
or with :bash:`vendor/bin/typo3 extension:setup`,
after the update. The change rewrites both tables. They hold the semesters and
modules of all study plans, which is rarely many rows.

An installation that redefined the column in an :file:`ext_tables.sql` of its
own, as a float column for example, removes that definition before running
the compare. A definition of an extension loaded later, such as a site package
that depends on this one, takes precedence, so the column would otherwise stay
as it is. A TCA override that only adds :php:`'format' => 'decimal'` is no
longer needed.

.. index:: Backend, Database, Frontend, TCA, ext:academic_study_plan