Doc: clarify use of NULL to drop comments and security labels.
This was only mentioned in the description of the text/label, which
are marked as being in quotes in the synopsis, which can cause
confusion (as witnessed on IRC).
Also separate the literal and NULL cases in the parameter list, per
suggestion from Tom Lane.
Also add an example of dropping a security label.
Dagfinn Ilmari Mannsåker, with some tweaks by me
Discussion: https://postgr.es/m/87sffqk4zp.fsf@wibble.ilmari.org
Branch
------
REL_11_STABLE
Details
-------
https://git.postgresql.org/pg/commitdiff/c1827e9cd2d70a353c066b1b70961e514ebe1d9f
Modified Files
--------------
doc/src/sgml/ref/comment.sgml | 16 ++++++++++++----
doc/src/sgml/ref/security_label.sgml | 29 ++++++++++++++++++++++-------
2 files changed, 34 insertions(+), 11 deletions(-)