Re: [DOCS] Doc BUG and/or Change Request: Include Postgres's systemcolumns in reserved words in docs, Chnage to previx sytem colums with 2 underscores? - Mailing list pgsql-docs
From
David G. Johnston
Subject
Re: [DOCS] Doc BUG and/or Change Request: Include Postgres's systemcolumns in reserved words in docs, Chnage to previx sytem colums with 2 underscores?
2017-10-02 22:30 GMT-03:00 dan d <dano2k3@hotmail.com>: > Npgsql.PostgresException (0x80004005): 42701: column name "cmax" conflicts > with a system column name > > My first step was to google "Postgres Reserved Words" will eventually get > you to Appendix C in the doc but not mention about any system columns, url > for help page: > > https://www.postgresql.org/docs/9.6/static/sql-keywords-appendix.html > The title is clear: *SQL* Key Words. It is not *PostgreSQL* Key Words. BTW, system columns are documented [1].
That's a bit unconvincing since there are words on that table that are not marked as being reserved in any of the three SQL standard columns.
Its user-error that an error message clearly indicating "system column name" prompted a search for reserved words instead of "system columns".
The main distinction here is that "cmax" is a valid identifier expect when used as a table column name (you can, for instance, name columns of CTEs cmax) due to it already being in use. Given the clarity of the error message and the fact that this is first I've seen the particular complaint in many years of monitoring these lists, I'd say trying to add system columns to the listing of reserved words in the interest of "comprehensiveness" doesn't outweigh the complexity that would be introduced explaining how it differs from other reserved words.
I wouldn't be opposed to adding a sentence and cross-reference link to the system columns page and pointing out that specific column names are also already reserved for system use.
