Thread: Documentation on pgdump(1) uses "regular expression" instead of "psql pattern"
Documentation on pgdump(1) uses "regular expression" instead of "psql pattern"
From
PG Doc comments form
Date:
The following documentation comment has been logged on the website: Page: https://www.postgresql.org/docs/14/app-pgdump.html Description: Hello. the [1] uses term "regular expression" where "psql pattern" [2] should be used instead which may be misleading (and might cause even some harm in some edge usage cases). I therefor propose to improve the documentation by emphasizing (strongly) the fact that the "regular expression" is in fact (psql) "pattern" and have nothing to do with *common* regular expressions and therefor extra care should be taken when using them. (From my point of view, the best would be to lead the reader directly to the [2], preferably somewhere at the beginning of the document/page, and also mention it again in the section with the examples by replacing the wrong term "regular expressions" with "patterns" hyperlinked to [2].) - [1] https://www.postgresql.org/docs/current/app-pgdump.html#PG-DUMP-EXAMPLES - [2] https://www.postgresql.org/docs/current/app-psql.html#APP-PSQL-PATTERNS Sincerely, -- mjf
Re: Documentation on pgdump(1) uses "regular expression" instead of "psql pattern"
From
Tom Lane
Date:
PG Doc comments form <noreply@postgresql.org> writes:
> the [1] uses term "regular expression" where "psql pattern" [2] should be
> used instead which
> may be misleading (and might cause even some harm in some edge usage
> cases).
> I therefor propose to improve the documentation by emphasizing (strongly)
> the fact that the
> "regular expression" is in fact (psql) "pattern" and have nothing to do with
> *common* regular
> expressions and therefor extra care should be taken when using them.
Hmm. I looked at this but I think that the existing wording is fine.
The definitions of the switches, earlier on the same page, correctly
state that they use psql-style patterns, and provide cross-references
to that documentation. Moreover, the context of this is that the
preceding example already uses shell-pattern notation:
To dump all schemas whose names start with east or west and end in
gsm, excluding any schemas whose names contain the word test:
$ pg_dump -n 'east*gsm' -n 'west*gsm' -N '*test*' mydb > db.sql
The same, using regular expression notation to consolidate the switches:
$ pg_dump -n '(east|west)*gsm' -N '*test*' mydb > db.sql
We could write something wishy-washy like "additional pattern-matching
notation", but the psql Patterns section specifically uses "regular
expression notation" to describe these extensions to normal shell
patterns, and that's completely correct because they *are* standard
regular expression notations. So I think being consistent with that
is more useful than writing something else. Also, we have five
cross-references to Patterns on that page already, so I don't think
a sixth would add much.
regards, tom lane