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0 pointsTerr_8y ago0 comments

> Finally, hash indexes always require that the found row be confirmed in the data table

Probably to avoid returning the wrong result for statistically-inevitable collisions, right?

0 comments

Probably it is needed to check if the row is still visible to that transaction.

Postgres uses a visibility bitmap [1] to avoid hitting the heap merely to determine visibility of stable data.

Correct.

j / k navigate · click thread line to collapse

0 pointsTerr_8y ago0 comments

> Finally, hash indexes always require that the found row be confirmed in the data table

Probably to avoid returning the wrong result for statistically-inevitable collisions, right?

Probably it is needed to check if the row is still visible to that transaction.

Postgres uses a visibility bitmap [1] to avoid hitting the heap merely to determine visibility of stable data.

Correct.

j / k navigate · click thread line to collapse