Re: psql - -dry-run option

2015-12-17 20:14 GMT+01:00 Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com>:

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> 2015-12-17 20:03 GMT+01:00 Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>:
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>> Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com> writes:
>> > when I read a blog
>> >
>> http://www.depesz.com/2015/12/14/waiting-for-9-6-psql-support-multiple-c-and-f-options-and-allow-mixing-them/
>> > where is emulated dry-run mode, I though so we can implement it very
>> > simply.
>>
>> Not one that is actually reliable. All a script would have to do is
>> include its own begin/commit commands, and it would override what you
>> are talking about. It's okay, in my opinion, if the -1 switch is just a
>> half-baked "best effort" solution. It's not okay to provide a --dry-run
>> switch that is equally full of holes, because if someone were to actually
>> rely on it to not execute the script, the possibility of an override would
>> amount to a security bug.
>>
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> My idea was enforce global transaction (-1) option and ensure
> STOP_ON_ERROR mode (cannot be changed later). Any inner COMMIT or ROLLBACK
> have to be disallowed (or ignored) - what can be problem :(
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> and if all statements from input stream was processed, then ROLLBACK is
> emitted, but result is success.
>
> Pavel
>

or different idea - just enforce syntax check without execution.

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>> regards, tom lane
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