In docs/alternator/compatibility.md we said that although Alternator
supports authentication, it doesn't support authorization (access
control). Now it does, so the relevant text needs to be corrected
to fit what we have today.
It's still in the compatibility.md document because it's not the same
API as DynamoDB's, so users with existing applications may need to be
aware of this difference.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
This commit removes the 5.4-to-6.0 upgrade guide and all references to it.
It mainly removes references to the Enable Consistent Topology Updates page,
which was added as enabling the feature was optional.
In rare cases, when a reference to that page is necessary,
the internal link is replaced with an external link to version 6.0.
Especially the Handling Cluster Membership Change Failures page was modified
for troubleshooting purposes rather than removed.
Separate keyspace which also behaves as system brings
little benefit while creating some compatibility problems
like schema digest mismatch during rollback. So we decided
to move auth tables into system keyspace.
Fixes https://github.com/scylladb/scylladb/issues/18098Closesscylladb/scylladb#18769
This commit includes updates related to replacing system_auth with system_auth_v2.
- The keyspace name system_auth is renamed to system_auth_v2.
- The procedures are updated to account for system_auth_v2.
- No longer required system_auth RF changes are removed from procedures.
- The information is added that if the consistent topology updates feature
was not enabled upon upgrade from 5.4, there are limitations or additional
steps to do (depending on the procedure).
The files with that kind of information are to be found in _common folders
and included as needed.
- The upgrade guide has been updated to reflect system_auth_v2 and related impacts.
Closesscylladb/scylladb#18077
This patch adds to docs/alternator/compatibility.md mentions of three
recently-added DynamoDB features (ReturnValuesOnConditionCheckFailure,
DeletionProtectionEnabled and TableClass) which Alternator does not yet
support.
Each of these mentions also links to the github issue we have on each
feature - issues #14481, #14482 and #10431 respectively.
During a review of this patch, the reviewers didn't like that I used
words like "recent" and "new" to describe recently-added DynamoDB
features, and asked that I use specific dates instead. So this is what
I do in this patch for the new features - and I also went back and
fixed a few pre-existing references to "recent" and "new" features,
and added the dates.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#14483
docs/alternator/compatibility.md mentions a known problem that
Alternator Streams are divided into too many "shards". This patch
add a link to a github issue to track our work on this issue - like
we did for most other differences mentioned in compatibility.md.
Refs #13080
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#13081
This PR adds a note to the Alternator TTL section to specify in which Open Source and Enterprise versions the feature was promoted from experimental to non-experimental.
The challenge here is that OSS and Enterprise are (still) **documented together**, but they're **not in sync** in promoting the TTL feature: it's still experimental in 5.1 (released) but no longer experimental in 2022.2 (to be released soon).
We can take one of the following approaches:
a) Merge this PR with master and ask the 2022.2 users to refer to master.
b) Merge this PR with master and then backport to branch-5.1. If we choose this approach, it is necessary to backport https://github.com/scylladb/scylladb/pull/11997 beforehand to avoid conflicts.
I'd opt for a) because it makes more sense from the OSS perspective and helps us avoid mess and backporting.
Closes#12295
* github.com:scylladb/scylladb:
doc: fix the version in the comment on removing the note
doc: specify the versions where Alternator TTL is no longer experimental
The docs/alternator/compatibility.md file links to various open issues
on unimplemented features. One of the links was to an already-closed
issue. Replace it by a link to an open issue that was missing.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#12649
The alternator compatibility.md document mentions the missing ACL
(access control) feature, but unlike other missing features we
forgot to link to the open issue about this missing feature.
So let's add that link.
Refs #5047.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#12399
In August 2022, DynamoDB added a "S3 Import" feature, which we don't yet
support - so let's document this missing feature in the compatibility
document.
Refs #11739.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#11740
In compatibility.md where we refer to the missing ability to add a GSI
to an existing table - let's refer to a new issue specifically about this
feature, instead of the old bigger issue about UpdateItem.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#11568
This commit introduces the following changes to Alternator compability doc:
* As of https://github.com/scylladb/scylladb/pull/11298 Alternator will return ProvisionedThroughput in DescribeTable API calls. We add the fact that tables will default to a BillingMode of PAY_PER_REQUEST (this wasn't made explicit anywhere in the docs), and that the values for RCUs/WCUs are hardcoded to 0.
* Mention the fact that ScyllaDB (thus Alternator) hashing function is different than AWS proprietary implementation for DynamoDB. This is mostly of an implementation aspect rather than a bug, but it may cause user confusion when/if comparing the ResultSet between DynamoDB and Alternator returned from Table Scans.
Refs: https://github.com/scylladb/scylladb/issues/11222
Fixes: https://github.com/scylladb/scylladb/issues/11315Closes#11360
In issue #10966, a user noticed that Alternator writes may be reordered
(a later write to an item is ignored with the earlier write to the same
item "winning") if Scylla nodes do not have synchronized time and if
always_use_lwt write isolation mode is not used.
In this patch I add to docs/alternator/compatibility.md a section about
this issue, what causes it, and how to solve or at least mitigate it.
Fixes#10966
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#11094
Currently in docs/alternator/compatibility.md experimental features
and unimplemented features are bunched together under one heading
("unimplemented features"). In this patch we separate them into two
sections. This makes the "unimplemented features" section shorter,
and also allows us to link to the new "experimental features" section
separately.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#10893
This patch implements the previously-unimplemented Select option of the
Query and Scan operators.
The most interesting use case of this option is Select=COUNT which means
we should only count the items, without returning their actual content.
But there are actually four different Select settings: COUNT,
ALL_ATTRIBUTES, SPECIFIC_ATTRIBUTES, and ALL_PROJECTED_ATTRIBUTES.
Five previously-failing tests now pass, and their xfail mark is removed:
* test_query.py::test_query_select
* test_scan.py::test_scan_select
* test_query_filter.py::test_query_filter_and_select_count
* test_filter_expression.py::test_filter_expression_and_select_count
* test_gsi.py::test_gsi_query_select_1
These tests cover many different cases of successes and errors, including
combination of Select and other options. E.g., combining Select=COUNT
with filtering requires us to get the parts of the items needed for the
filtering function - even if we don't need to return them to the user
at the end.
Because we do not yet support GSI/LSI projection (issue #5036), the
support for ALL_PROJECTED_ATTRIBUTES is a bit simpler than it will need
to be in the future, but we can only finish that after #5036 is done.
Fixes#5058.
The most intrusive part of this patch is a change from attrs_to_get -
a map of top-level attributes that a read needs to fetch - to an
optional<attrs_to_get>. This change is needed because we also need
to support the case that we want to read no attributes (Select=COUNT),
and attrs_to_get.empty() used to mean that we want to read *all*
attributes, not no attributes. After this patch, an unset
optional<attrs_to_get> means read *all* attributes, a set but empty
attrs_to_get means read *no* attributes, and a set and non-empty
attrs_to_get means read those specific attributes.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20220405113700.9768-2-nyh@scylladb.com>
The document docs/alternator/compatibility.md suggested that Alternator
does not support the TTL feature at all. The real situation is more
optimistic - this feature is supported, but as experimental feature.
So let's update compatibility.md with the real status of this feature.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Now that issues #7586 and #9487 were fixed, reverse queries - even in
long partitions - work well, we can drop the claim in
alternator/docs/compatibility.md that reverse queries are buggy for
large partitions.
We can also remove the "xfail" mark from the tes that checks this
feature, as it now passes.
Refs #7586
Refs #9487
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#9831
In the last year, four new features were added to DynamoDB which we
don't yet support - Kinesis Streams, PartiQL, Contributor Insights and
Export to S3. Let's document them as missing Alternator features, and
point to the four newly-created issues about these features.
Refs #8786
Refs #8787
Refs #8788
Refs #8789
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20210603125825.1179171-1-nyh@scylladb.com>
We had Alternator's current compatibility with DynamoDB described in
two places - alternator.md and compatibility.md. This duplication was
not only unnecessary, in some places it led to inconsistent claims.
In general, the better description was in compatibility.md, so in
this patch we remove the compatibility section from alternator.md
and instead link to compatibility.md. There was a bit of information
that was missing in compatibility.md, so this patch adds it.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20210215203057.1132162-1-nyh@scylladb.com>
This patch adds full support for nested attribute paths (e.g., a.b[3].c)
in UpdateExpression. After in previous patches we already added such
support for ProjectionExpression, ConditionExpression and FilterExpression
this means the nested attribute paths feature is now complete, so we
remove the warning from the documents. However, there is one last loose
end to tie and we will do it in the next patch: After this patch, the
combination of UpdateExpression with nested attributes and ReturnValues
is still wrong, and the test for it in test_returnvalues.py still xfails.
Note that previous patches already implemented support for attribute paths
in expression evaluations - i.e., the right-hand side of UpdateExpression
actions, and in this patch we just needed to implement the left hand side:
When an update action is on an attribute a.b we need to read the entire
content of the top-level a (an RWM operation), modify just the b part of
its json with the result of the action, and finally write back the entire
content of a. Of course everything gets complicated by the fact that we
can have multiple actions on multiple pieces of the same JSON, and we also
need to detect overlapping and conflicting actions (we already have this
detection in the attribute_path_map<> class we introduced in a previous
patch).
I decided to leave one small esoteric difference, reproduced by the xfailing
test_update_expression.py::test_nested_attribute_remove_from_missing_item:
As expected, "SET x.y = :val" fails for an item if its attribute x doesn't
exist or the item itself does not exist. For the update expression
"REMOVE x.y", DynamoDB fails if the attribute x doesn't exist, but oddly
silently passes if the entire item doesn't exist. Alternator does not
currently reproduce this oddity - it will fail this write as well.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Add to the DynamoDB compatibility document, docs/alternator/compatibility.md,
a mention that Alternator streams are still an experimental features, and
how to turn it on (at this point CDC is no longer an experimental feature,
but Alternator Streams are).
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20201112184436.940497-1-nyh@scylladb.com>
This patch adds a new document, docs/alternator/compatibility.md,
which focuses on what users switching from DynamoDB to Alternator
need to know about where Alternator differs from DynamoDB and which
features are missing.
The compatibility information in the old alternator.md is not deleted
yet. It probably should.
Fixes#7556
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20201110180242.716295-1-nyh@scylladb.com>
