On 03/03/2018 01:56 AM, Tom Lane wrote:
> Tomas Vondra <tomas.vondra@2ndquadrant.com> writes:
>> OK, time to revive this old thread ...
>>>> [ scalarineqsel may fall over when used by extension operators ]
>
>> Attached is a minimal fix adding a flag to convert_numeric_to_scalar,
>> tracking when it fails because of unsupported data type. If any of the 3
>> calls (value + lo/hi boundaries) sets it to 'true' we simply fall back
>> to the default estimate (0.5) within the bucket.
>
> I think this is a little *too* minimal, because it only covers
> convert_numeric_to_scalar and not the other sub-cases in which
> convert_to_scalar will throw an error instead of returning "false".
> I realize that that would be enough for your use-case, but I think
> we need to think more globally. So please fix the other ones too.
>
Will do.
> I notice BTW that whoever shoehorned in the bytea case failed to
> pay attention to the possibility that not all three inputs are
> of the same type; so that code is flat out broken, and capable
> of crashing if fed dissimilar types. We ought to deal with that
> while we're at it, since (IMO) the goal is to make convert_to_scalar
> fail-soft for any combination of supplied data types.
>
OK, I'll look into that too.
regards
--
Tomas Vondra http://www.2ndQuadrant.com
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