This adds a find_index_nomame() helper to the schema class, which
searches for index that is otherwise equal but ignores the name of the
index in comparison. This is needed to for CREATE INDEX to reject
duplicate index creation.
The write path uses a base schema at a particular version, and we
want it to use the materialized views at the corresponding version.
To achieve this, we need to map the state currently in db::view::view
to a particular schema version, which this patch does by introducing
the view_info class to hold the state previously in db::view::view,
and by having a view schema directly point to it.
The changes in the patch are thus:
1) Introduce view_info to hold the extra view state;
2) Point to the view_info from the schema;
3) Make the functions in the now stateless db::view::view non-member;
4) Remove the db::view::view class.
All changes are structural and don't affect current behavior.
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
In preparation for upcoming patches, which will deal with
moving the state in db::view::view to view_info.
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
This patch ensures that changes to a base table's schema
are reflected in that table's materialized views.
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
The view_ptr class contains a schema_ptr known to represent a
materialized view. It is intended to be used by functions that require
such a schema, and thus obviate the need for the function to check for
schema::is_view().
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
This patch adds a view_info optional field to the schema. It's
presence indicates the schema represents a materialized view.
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
column_mapping is not safe to access across shards, because data_type
is not safe to access. One of the manifestation of this is that
abstract_type::is_value_compatible_with() always fails if the two
types belong to different shards.
During replay, column_mapping lives on the replaying shard, and is
used by converting_mutation_partition_applier against the schema on
the target shard. Since types in the mapping will be considered
incompatible with types in the schema, all cells will be dropped.
Fix by using column_mapping in a safe way, by copying it to the target
shard if necessary. Each shard maintains its own cache of column
mappings.
Fixes#1924.
Message-Id: <1481310463-13868-1-git-send-email-tgrabiec@scylladb.com>
This patch extracts the definition of the default compressor into the
compression_parameters class, so that the table and view creation
statements don't have to explicitly deal with it.
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
This is a confusing one, and can be replaced the fact that dense
schemas have a single regular column.
Ref #1542
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
A compact column is a dense schema's single regular column. The fact
that it is a different column_kind has lead to various bugs (#1535,
derived by the schema being dense and the column being regular.
Fixes#1542
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
This patch adds the is_dynamic() function to thrift_schema, which
tells whether the underlying column family is dynamic or not,
according to thrift rules.
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
is_atomic() is called for each cell in mutation applies, compaction
and query. Since the value doesn't change it can be easily cached which
would save one indirection and virtual call.
Results of perf_simple_query -c1 (median, duration 60):
before after
read 54611.49 55396.01 +1.44%
write 65378.92 68554.25 +4.86%
Signed-off-by: Paweł Dziepak <pdziepak@scylladb.com>
Message-Id: <1465991045-11140-1-git-send-email-pdziepak@scylladb.com>
Cassandra disallows adding a column with the same name as a collection
that existed in the past in that table if the types aren't compatible.
To enforce that Scylla needs to keep track of all collections that ever
existed in the column family.
Signed-off-by: Paweł Dziepak <pdziepak@scylladb.com>
When a column is dropped its name and deletion timestamp are added
to schema::_raw._dropped_columns to prevent data resurrection in case a
column with the same name is added. To reduce the number of lookups in
_dropped_columns this patch makes each instance of column_definition
to caches this information (i.e. timestamp of the latest removal of a
column with the same name).
Signed-off-by: Paweł Dziepak <pdziepak@scylladb.com>
Knowing which columns were dropped (and when) is important to prevent
the data from the dropped ones reappearing if a new column is added with
the same name.
Signed-off-by: Paweł Dziepak <pdziepak@scylladb.com>
We want the node's schema version to change whenever
table_schema_version of any table changes. The latter is calculated by
hashing mutations so we should also use mutation hash when calculating
schema digest.
We need to track which schema version were synced with on current node
to avoid triggering the sync on every mutation. We need to sync before
mutating to be able to apply the incoming mutation using current
node's schema, possibly applying irreverdible transformations to it to
make it conform.
Right now in some places we use column_id, and in some places
size_t. Solve it by using column_count_type whose meaning is "an
integer sufficiently large for indexing columns". Note that we cannot
use column_id because it has more meaning to it than that.
The version needs to change value not only on structural changes but
also temporal. This is needed for nodes to detect if the version they
see was already synchronized with or not even if it has the same
structure as the past versions. We also need to end up with the same
version on all nodes when schema changes are commuted.
For regular mutable schemas version will be calculated from underlying
mutations when schema is announced. For static schemas of system
keyspace it is calculated by hashing scylla version and column id,
because we don't have mutations at the time of building the schema.
For static and regular (row) columns it is very convenient in some
cases to utilize the fact that columns ordered by ids are also ordered
by name. It currently holds, so make schema export this guarantee and
enable consumers to rely on.
The static schema::row_column_ids_are_ordered_by_name field is about
allowing code external to schema to make it very explicit (via
static_assert) that it relies on this guarantee, and be easily
discoverable in case we would have to relax this.
