Re: [bug fix] Savepoint-related statements terminates connection

On 17 May 2017 at 08:38, Tsunakawa, Takayuki
<tsunakawa(dot)takay(at)jp(dot)fujitsu(dot)com> wrote:
> From: Michael Paquier [mailto:michael(dot)paquier(at)gmail(dot)com]
>> On Fri, Mar 31, 2017 at 9:58 PM, Ashutosh Bapat
>> <ashutosh(dot)bapat(at)enterprisedb(dot)com> wrote:
>> > Then the question is why not to allow savepoints as well? For that we
>> > have to fix transaction block state machine.
>>
>> I agree with this argument. I have been looking at the patch, and what it
>> does is definitely incorrect. Any query string including multiple queries
>> sent to the server is executed as a single transaction. So, while the current
>> behavior of the server is definitely incorrect for savepoints in this case,
>> the proposed patch does not fix anything but actually makes things worse.
>> I think that instead of failing, savepoints should be able to work properly.
>> As you say cursors are handled correctly, savepoints should fall under the
>> same rules.
>
> Yes, I'm in favor of your opinion. I'll put more thought into whether it's feasible with invasive code.

I'm not sure I see the use case for anyone using SAVEPOINTs in this
context, so simply throwing a good error message is enough.

Clearly nobody is using this, so lets just lock the door. I don't
think fiddling with the transaction block state machine is anything
anybody wants to do in back branches, at least without a better reason
than this.

Simpler version of original patch attached.

--
Simon Riggs http://www.2ndQuadrant.com/
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