Re: [BUG] false positive in bt_index_check in case of short 4B varlena datum

Hi Alexander,

20.03.2024 13:24, Alexander Korotkov wrote:
> BTW, 0001 and 0002 look good to me. I'm going to push them if no objections.

Maybe these patches should be polished before committing:
+-- directory paths are passed to us in environment variables
looks like an irrelevant change (perhaps it was relevant in v1/v2, but
that's not so now.)

I'm also not sure about:
+-- BUG: must support different header size of short varlena datum
+-- https://postgr.es/m/7bdbe559-d61a-4ae4-a6e1-48abdf3024cc@postgrespro.ru

AFAICS, for most similar bug fixes, the bug report referenced in a commit
message only (there is no such comment in 0002, either). I also suspect
that the comment:
* Also tuple had short varlena datums with 4B header. ...
might looks incorrect for native English speakers.

This patch also adds a couple of empty lines, which may be not needed.
@@ -2973,6 +2973,7 @@ bt_normalize_tuple(BtreeCheckState *state, IndexTuple itup)
         * index without further processing, so an external varlena header
         * should never be encountered here
         */
> +
        if (VARATT_IS_EXTERNAL(DatumGetPointer(normalized[i])))
            ereport(ERROR,
                    (errcode(ERRCODE_INDEX_CORRUPTED),
---
        }
+       /*
...
+           need_free[i] = true;
+       }
> +
    }

Best regards,
Alexander