There are several different object types in a versioned table,
which will determine the exact behaviour.
The object type states are:
* Pending - the object is yet to be committed and is being uploaded.
* Committed - the object has been finished and can be read.
* DeleteMarker - indicates that the object should be treated as not
present when is at the top of the version stack.
There are also versioning states:
* Unversioned - only one unversioned object is allowed per object key.
* Versioned - multiple objects with the same key are allowed.
Change-Id: I65dfa781e8da253a4e5d572b799d53c351196eee
There's only one value that BeginExactObject should return and there's
no point in restating that.
Also, use a clearer value for the random object version.
Change-Id: I06b26ad87d64e1b04b48458f624edd630f7f2f1d
Current metainfo.ListObjects implementation is using metabase iterator to list objects.
In the non-recursive case, it used to retrieve all the corresponding rows and then discarded the entries that did not fit the listing request.
This can lead in some edge cases (each prefix contains more than batchsize objects/sub-prefixes) to make unecessary calls to the db.
This change defines the metabase.ListObjects and aims at retrieving only prefixes (but not objects under it) and objects by modifying the SQL query.
In this version, it is not optimized on the database side. Cockroach will still have to go through all rows under a prefix, so there is still room for improvement.
metainfo.ListObjects is not currently using this method as we would like to assess its performance on the QA satellite first.
Fixes https://github.com/storj/storj/issues/5088
Change-Id: Ied3a9210871871d9d4a3096888d3e40c2dceed61
