It's not enough to back up each index's translation keys after
backing up that index's data; we also have to back them up after
backing up any index data from indexes which have foreign key
references to that index. So we do the per-index passes separately.
Since the individual backup data files are being created separately,
the expected output is unchanged for a quiescent database, the only
difference is that the amount of translation info which might be
newer than the data stored for shards is potentially increased.
Previously the backup tool only fsync'ed the files.
Since the directories were not synced, it was possible for the references to be lost.
Now we sync the entire output directory tree and its parent.
Attributes are unmaintained and unused.
They have become more of a liability than a benefit.
This change eliminates them from the codebase.
The only user-visible change (assuming that attrs are not used) is that the attrs field will no longer appear in row JSON.
Previously, multiple frames with different prefixes were used to separate
different data layouts. This included separating standard row/column
layouts from inverted column/row layouts as well as storing aggregate
information for timestamp data.
Unfortunately, this caused frame meta data to be copied between multiple
frames and it made it difficult to keep these frames in sync.
This commit separates these different physical layouts into `Views`.
A `Frame` now has one or more views which represent each layout.
Fragments have been moved from under the `Frame` to be contained
within the `View`.
There are two primary views:
- `standard`
- `inverse`
If a frame has a time quantum, then views are generated for these
each of the standard/inverse views. For example a time quantum
of `YMDH` for the date `2000-01-02T00:00:00Z` would create the
following views:
- `standard_2000`
- `inverse_2000`
- `standard_200001`
- `inverse_200001`
- `standard_20000102`
- `inverse_20000102`
From the user's perspective, nothing should change in PQL. Different
PQL statements will handle the appropriate view automatically. For
example, `Bitmap()` and `Profile()` will fetch using the `standard`
view or the `inverse` view, respectively. The `Range()` statement
will lookup the appropriate time-based views automatically.
