Обсуждение: currentItemData & currentMarkData

It has bothered me for some time that we have currentItemData and 
currentMarkData fields in IndexScanDescData, while it's really indexam's 
private data. They should be in the indexam opaque structure.

At the moment, they're used in gist and hash access methods, and they're 
not used in b-tree and gin. The new bitmap index code uses them, but 
only as an internal boolean flag indicating that the scan has been 
initialized, so that should be fixed anyway.

How about removing those fields from IndexScanDesc?

There's also is_multiscan field which is set but never read.

-- 
Heikki Linnakangas
EnterpriseDB http://www.enterprisedb.com

Heikki Linnakangas <heikki@enterprisedb.com> writes:
> It has bothered me for some time that we have currentItemData and 
> currentMarkData fields in IndexScanDescData, while it's really indexam's 
> private data. They should be in the indexam opaque structure.

Can't get very excited about it, but if you want.

> There's also is_multiscan field which is set but never read.

It has been needed in the past and could plausibly be needed again
sometime --- an index AM's rescan method might want to know what kind
of scan it's setting up for.  Of course, if we get rid of amgetmulti
entirely as has been discussed, this'd go away too.
        regards, tom lane