Re: chained transactions

On 2019-02-16 06:22, Andres Freund wrote:
>> +static int	save_XactIsoLevel;
>> +static bool	save_XactReadOnly;
>> +static bool	save_XactDeferrable;
> 
> We normally don't define variables in the middle of a file?  Also, why
> do these need to be global vars rather than defined where we do
> chaining? I'm imagining a SavedTransactionState struct declared on the
> stack that's then passed to Save/Restore?
> 
> Not crucial, but I do wonder if we can come up with a prettier approach
> for this.

If we do it with a struct that is passed to the functions, then either
the struct contents will be available outside of xact.c, which will
expose internals of xact.c that weren't previously exposed, or we do it
with an incomplete struct, but then this would involve palloc across
transaction commit, resulting in additional complexity.  Neither of
these sound like obviously better alternatives.

-- 
Peter Eisentraut              http://www.2ndQuadrant.com/
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