CYCPOINTS is special in that the
presence of a Ddate row can trigger the automatic generation of
a Mdate row 13 days later. Automatically generated Mdates are
distinguished by having a CYCPOINTS.Source of A.
As Ddate rows are inserted, updated, or deleted Babase makes
appropriate changes to ensure that automatically generated Mdate
rows exist on the 13th day following a qualified Ddate. The
exception is when a Tdate follows a Ddate by less than 13 days
(and there are no intervening gaps in observation.) In this
case the automatically generated Mdate will have the Tdate's
date and be less than 13 days after the previous Ddate.
An Mdate will be generated from a Ddate when all of the following conditions are met:
Either there is no Mdate in the cycle following the Ddate's cycle or there is a gap in observation between the Ddate's cycle and the following cycle.
The Ddate is not the start of a pregnancy, its Cpid does not appear as a Conceive value on the PREGS table.
Observation proceeds without a gap for at least 13 days following the Ddate, or up to the Tdate immediately following the Ddate, which ever comes first,
The Ddate is not estimated. (Source is not
E)
The individual is alive (BIOGRAPH.Status is
0) on the automatic Mdate.[227]
A Mdate automatically generated from a Ddate will be
removed when any of the above conditions are no longer met, or
when another Mdate is automatically generated for the
Ddate.[228]More precisely, it is not a Mdate automatically
generated from a Ddate that will be removed but rather any Mdate
will be removed that has a Source of
A, and that post-dates the Ddate, and
that has no Mdates, Tdates, or Ddates, or periods of no
observation (see CYCGAPS) on the interval
between the Ddate and the “automatic” Mdate.
Babase cannot distinguish manually entered Mdates with a Source of A
from automatically generated Mdates. Therefore it is not just
automatically generated Mdates that will be removed.
Automatically assigned Mdates, those with a
Cycpoints-Source of A, have NULL
Edates and Ldates.
[227] This means that automatic Mdates may occur after an individual's Statdate, so long as the individual is alive.
[228] So, there does not have to be a special rule to change the date of automatically generated Mdates in response to changes in the Ddates that generated them. Altering the Ddate creates a new Mdate, and in response the old Mdate is removed.