Re: Statistics Import and Export

On Sat, 2025-02-22 at 00:00 -0500, Corey Huinker wrote:
>
> Attached is the first optimization, which gets rid of the pg_class
> queries entirely, instead getting the same information from the
> existing queries in getTables and getIndexes.

Attached a revised version. The main changes are that the only struct
it changes is RelStatsInfo, and it doesn't carry around string values.

IIUC, your version carried around the string values so that there would
be no conversion; it would hold the string from one result to the next.
That makes sense, but it seemed to change a lot of struct fields, and
have unnecessary string copying and memory usage which was not freed.
Instead, I used float_to_shortest_decimal_buf(), which is what
float4out() uses, which should be a consistent way to convert the float
value.

That meant that we couldn't use appendNamedArgument() as easily, but it
wasn't helping much in that function anyway, because it was no longer a
loop.

I didn't measure any performance difference between your version and
mine, but avoiding a few allocations couldn't hurt. It seems to save
just under 20% on an unoptimized build.

Regards,
Jeff Davis