This patch enforces that vector indexes can only be created on keyspaces
that use tablets. During index validation, `check_uses_tablets()` verifies
the base keyspace configuration and rejects creation otherwise.
To support this, the `custom_index::validate()` API now receives a
`const data_dictionary::database&` parameter, allowing index
implementations to access keyspace-level settings during DDL validation.
Fixes https://scylladb.atlassian.net/browse/VECTOR-322Closesscylladb/scylladb#26786
We currently allow creating multiple vector indexes on one column.
This doesn't make much sense as we do not support picking one when
making ann queries.
To make this less confusing and to make our behavior similar
to Cassandra we disallow the creation of multiple vector indexes
on one column.
We also add a test that checks this behavior.
Fixes: VECTOR-254
Fixes: #26672Closesscylladb/scylladb#26508
Since creating the vector index does not lead to creation
of a view table [#24438] (whose version info had been logged in
`system_schema.scylla_tables`) we lack the information about
the version of the index.
The mentioned version is used to recognize the quick-drop-create
index with the same parameters that needs to be rebuild.
The case is mainly experienced while testing, benchmarking
or experimenting with Vector Search.
Nevertheless it is important to have it considered, as it is really
weird having seen that DROP and CREATE commands did not change
anything.
Although being nice "optimization" to use the same old index,
the rebuild feels more natural for the get-to-know-VS-users.
Should not change anything in a real production environment.
The solution we arrived at is to add the version as a field in
options column of `system_schema.indexes`.
The version of vector index is a base table's schema version
on which the index was created.
The table's schema version changes everytime a table is changed
meaning that CREATE INDEX or DROP INDEX statement also change it.
Every index has a different index version, so it allows to identify
them easily.
This patch implements the solution described above.
Ensure that the CDC used by Vector Search has at least 24h TTL
and delta mode is set to 'full' or postimage is enabled.
This setup is required by the Vector Store to work as intended.
The TTL of at least 24h is a rough estimate of the maximal time
needed for the full scan conducted by Vector Store to finish.
The delta mode set to 'full' or postimage enabled is needed
to read the values of vectors being written to the table,
so Vector Store can save them in the desired external index.
As the default we set TTL = 24h, delta = 'full', postimage = false.
Full delta is preffered option to log the vector values as it is less
costly and does not require additional read on write.
Add `has_vector_index` function to check if an index
on vector column using 'vector_index' custom index
class exists in the schema.
Co-authored-by: Michał Hudobski <michal.hudobski@scylladb.com>
Add parsing of `ANN OF` queries to the `select_statement` and
`indexed_table_select_statement` classes.
Add a placeholder for the implementation of external ANN queries.
Rename `should_create_view` to `view_should_exist` as it is used
not only to check if the view should be created but also if
the view has been created.
Co-authored-by: Dawid Pawlik <dawid.pawlik@scylladb.com>
Currently we create a view for every index, however
for currently supported custom index classes (vector_index)
that work is redundant, as we store the index in the external
service.
This patch adds a way for custom indexes to choose whether to
create a view when creating the index and makes it so that
for vector indexes the view is not created.
Currently, to describe an index we look at
a corresponding view. However for custom indexes
the view may not exist (as we are removing the views
from vector indexes). This commit adds a way for a custom
index class to override the default describing logic
and provides such an override for the vector_index
class.
In this patch we add an abstract class, "custom_index", with a validate() method.
Each CUSTOM INDEX class needs to implement a concrete subclass of custom_index
which is used to validate if this type of custom index class may be used,
and whether the optional parameters passed to it are valid.
We change the existing CUSTOM INDEX validation code to use this new mechanism.
Finally this patch implements one concrete subclass for vector index.
Before this patch, the custom index type "vector_index" was allowed,
but after this patch it gains more validation of its optional parameters
(we support 4 specific parameters, with some rules on their values).
Of course, the vector index isn't actually implemented in this patch,
we are just improving the validation of the index creation statement.
