====================
Friday, May 22, 2015
====================

Debugging Django queries
========================

Did you ever have to debug code like this?

.. code-block:: python

    from django.db.models import Q

    def is_learning_filter(prefix, a, b):
        if a is None:
            flt = Q(**{prefix+'start_date__isnull': False})
        else:
            flt = Q(**{prefix+'start_date__lte': a})
        if b is not None:
            flt &= Q(**{prefix+'end_date__isnull': True}) \
                | Q(**{prefix+'end_date__gte': b})
        return flt

    def add_filter(qs, pv):
        p = (pv.start_date, pv.end_date)
        flt = is_learning_filter('training__', *p)
        flt |= is_learning_filter('study__', *p)
        flt |= is_learning_filter('experience__', *p)
        qs = qs.filter(flt)
        return qs

Well, my trick is to print the raw SQL using something like this::

    logger.info("20150522 %s", qs.query)

Another problem is then that these queries tend to become rather
long. So I copy it to http://sqlformat.org/ where it becomes much more
readable.


Cannot activate textfields
==========================

In :func:`lino.core.dbtables.wildcard_data_elems` I removed the
following test::

  if not isinstance(f, fields.RichTextField):

Because it is no longer needed (since wildcard columns are now hidden
by default), and because it was the cause for :ticket:`255`
(TextFields cannot be selected manually unless specified explicitly).

This change has one side effect: tables whose :attr:`colum_names
<lino.core.tables.AbstractTable.colum_names>` is left to the default
value (``'*'``) will now again also show text fields among their
columns. To make text fields hidden, there must be at least one
explicit field specified.


The yearly amount of a budget entry
===================================

Fixed :ticket:`258` (Das jährliche TOTAL fehlt auf den Ausdrucken
(z.B. Steuer)).


name '_' is not defined
=======================

In :meth:`lino.core.site.Site.get_printable_context` I had removed a
series of names which (only!) now turned out to be used.


Why DurationField columns had no sum
====================================

Ticket :ticket:`206` is solved. It was because :meth:`format_sum
<lino.modlib.extjs.elems.FieldElement.format_sum>` did not do its
job. Added demo data to :mod:`lino.modlib.clocking` and a test case to
:mod:`lino_noi`.