Previously, if the user set a special variable such as ECHO to an
unrecognized value, psql would bleat but store the new value anyway, and
then fall back to a default setting for the behavior controlled by the
variable. This was agreed to be a not particularly good idea. With
this patch, invalid values result in an error message and no change in
state.
(But this applies only to variables that affect psql's behavior; purely
informational variables such as ENCODING can still be set to random
values.)
To do this, modify the API for psql's assign-hook functions so that they
can return an OK/not OK result, and give them the responsibility for
printing error messages when they reject a value. Adjust the APIs for
ParseVariableBool and ParseVariableNum to support the new behavior
conveniently.
In passing, document the variable VERSION, which had somehow escaped that.
And improve the quite-inadequate commenting in psql/variables.c.
Daniel Vérité, reviewed by Rahila Syed, some further tweaking by me
Discussion: https://postgr.es/m/7356e741-fa59-4146-a8eb-cf95fd6b21fb@mm
For simple boolean variables such as ON_ERROR_STOP, psql has for a long
time recognized variant spellings of "on" and "off" (such as "1"/"0"),
and it also made a point of warning you if you'd misspelled the setting.
But these conveniences did not exist for other keyword-valued variables.
In particular, though ECHO_HIDDEN and ON_ERROR_ROLLBACK include "on" and
"off" as possible values, none of the alternative spellings for those were
recognized; and to make matters worse the code would just silently assume
"on" was meant for any unrecognized spelling. Several people have reported
getting bitten by this, so let's fix it. In detail, this patch:
* Allows all spellings recognized by ParseVariableBool() for ECHO_HIDDEN
and ON_ERROR_ROLLBACK.
* Reports a warning for unrecognized values for COMP_KEYWORD_CASE, ECHO,
ECHO_HIDDEN, HISTCONTROL, ON_ERROR_ROLLBACK, and VERBOSITY.
* Recognizes all values for all these variables case-insensitively;
previously there was a mishmash of case-sensitive and case-insensitive
behaviors.
Back-patch to all supported branches. There is a small risk of breaking
existing scripts that were accidentally failing to malfunction; but the
consensus is that the chance of detecting real problems and preventing
future mistakes outweighs this.
existing for backend GUC variables, and use this to eliminate repeated
fetching/parsing of psql variables in psql's inner loops. In a trivial
test with lots of 'select 1;' commands, psql's CPU time went down almost
10%, although of course the effect on total elapsed time was much less.
Per discussion about how to ensure the upcoming FETCH_COUNT patch doesn't
cost any performance when not being used.
client-side AUTOCOMMIT mode now: '\set AUTOCOMMIT off' supports
SQL-spec commit behavior. Get rid of LO_TRANSACTION hack --- the
LO operations just work now, using libpq's ability to track the
transaction status. Add a VERBOSE variable to control verboseness
of error message display, and add a %T prompt-string code to show
current transaction-block status. Superuser state display in the
prompt string correctly follows SET SESSION AUTHORIZATION commands.
Control-C works to get out of COPY IN state.
now, my changes seem to work. Some possible minor bugs got squished
on the way but I can't be sure without more feedback from people who
really put the code to the test.
The new patch mostly simplifies variable handling and reduces code
duplication. Changes in the command parser eliminate some redundant
variables (boolean state + depth counter), replaces some
"else if" constructs with switches, and so on. It is meant to be
applied together with my previous patch, although I hope they don't
conflict; I went back to the CVS version for this one.
One more thing I thought should perhaps be changed: an IGNOREEOF
value of n will ignore only n-1 EOFs. I didn't want to touch this
for fear of breaking existing applications, but it does seem a tad
illogical.
Jeroen T. Vermeulen
Initdb help correction
Changed end/abort to commit/rollback and changed related notices
Commented out way old printing functions in libpq
Fixed a typo in alter table / alter column
rate
it's better than what used to be there.
* Does proper SQL "host variable" substitution as pointed out by Andreas
Zeugwetter (thanks): select * from :foo; Also some changes in how ':'
and ';' are treated (escape with \ to send to backend). This does
_not_
affect the '::' cast operator, but perhaps others that contain : or ;
(but there are none right now).
* To show description with a <something> listing, append '?' to command
name, e.g., \df?. This seemed to be the convenient and logical
solution.
Or append a '+' to see more useless information, e.g., \df+.
* Fixed fflush()'ing bug pointed out by Jan during the regression test
discussion.
* Added LastOid variable. This ought to take care of TODO item "Add a
function to return the last inserted oid, for use in psql scripts"
(under CLIENTS)
E.g.,
insert into foo values(...);
insert into bar values(..., :LastOid);
\echo $LastOid
* \d command shows constraints, rules, and triggers defined on the table
(in addition to indices)
* Various fixes, optimizations, corrections
* Documentation update as well
Note: This now requires snprintf(), which, if necessary, is taken from
src/backend/port. This is certainly a little weird, but it should
suffice
until a source tree cleanup is done.
Enjoy.
--
Peter Eisentraut Sernanders väg 10:115
