The functions which prepare schema change mutations (such as
`prepare_new_column_family_announcement`) would use internally
generated timestamps for these mutations. When schema changes are
managed by group 0 we want to ensure that timestamps of mutations
applied through Raft are monotonic. We will generate these timestamps at
call sites and pass them into the `prepare_` functions. This commit
prepares the APIs.
Instead of lengthy blurbs, switch to single-line, machine-readable
standardized (https://spdx.dev) license identifiers. The Linux kernel
switched long ago, so there is strong precedent.
Three cases are handled: AGPL-only, Apache-only, and dual licensed.
For the latter case, I chose (AGPL-3.0-or-later and Apache-2.0),
reasoning that our changes are extensive enough to apply our license.
The changes we applied mechanically with a script, except to
licenses/README.md.
Closes#9937
The database, keyspace, and table classes represent the replica-only
part of the objects after which they are named. Reading from a table
doesn't give you the full data, just the replica's view, and it is not
consistent since reconciliation is applied on the coordinator.
As a first step in acknowledging this, move the related files to
a replica/ subdirectory.
After previous patches there's a whole bunch of places that do
qp.proxy().data_dictionary()
while the data_dictionary is present on the query processor itself
and there's a public method to get one. So use it everywhere.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The schema_altering_statement declares this pure virtual method. This
patch changes its first argument from proxy into query processor and
fixes what compiler errors about.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Stop using database (and including database.hh) for schema related
purposes and use data_dictionary instead.
data_dictionary::database::real_database() is called from several
places, for these reasons:
- calling yet-to-be-converted code
- callers with a legitimate need to access data (e.g. system_keyspace)
but with the ::database accessor removed from query_processor.
We'll need to find another way to supply system_keyspace with
data access.
- to gain access to the wasm engine for testing whether used
defined functions compile. We'll have to find another way to
do this as well.
The change is a straightforward replacement. One case in
modification_statement had to change a capture, but everything else
was just a search-and-replace.
Some files that lost "database.hh" gained "mutation.hh", which they
previously had access to through "database.hh".
To be able to confine raft to the execution time of a statement we need to
move all schema access to the execution time as well. Since the
validation code access the schema lets run it during execution.
This commit adds a very basic support for user-defined functions
coded in wasm. The support is very limited (only a few types work)
and was not tested against reactor stalls and performance in general.
storage_proxy.hh is huge and includes many headers itself, so
remove its inclusions from headers and re-add smaller headers
where needed (and storage_proxy.hh itself in source files that
need it).
Ref #1.
Most of the schema altering statements implementations can now
stop calling for global migration manager instance and get it
from the query processor.
Here are the trivial cases when the query processor is just
avaiable at the place where it's needed.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Now when the only call to .announce_migration gas the
query processor at hands -- pass it to the real statements.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
It looks like the history of the flag begins in Cassandra's
https://issues.apache.org/jira/browse/CASSANDRA-7327 where it is
introduced to speedup tests by not needing to start the gossiper.
The thing is we always start gossiper in our cql tests, so the flag only
introduce noise. And, of course, since we want to move schema to use raft
it goes against the nature of the raft to be able to apply modification only
locally, so we better get rid of the capability ASAP.
Tests: units(dev, debug)
Message-Id: <20201230111101.4037543-2-gleb@scylladb.com>
cql3 has cql_statement, parsed_statement and prepared_statement
classes, which, largely, stand for the same thing. prepared was
an alias for prepared_statement which only required an extra
tag jump in IDE and carried no meaning.
cql_statement is a class representing a prepared statement in Scylla.
It is used concurrently during execution, so it is important that its
change is not changed by execution.
Add const qualifier to the execution methods family, throghout the
cql hierarchy.
Mark a few places which do mutate prepared statement state during
execution as mutable. While these are not affecting production today,
as code ages, they may become a source of latent bugs and should be
moved out of the prepared state or evaluated at prepare eventually:
cf_property_defs::_compaction_strategy_class
list_permissions_statement::_resource
permission_altering_statement::_resource
property_definitions::_properties
select_statement::_opts
This add a wrapper around the lua interpreter so that function
executions are interruptible and return futures.
With this patch it is possible to write and use simple UDFs that take
and return integer values.
Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
With this it is possible to create user defined functions and
aggregates and they are saved to disk and the schema change is
propagated.
It is just not possible to call them yet.
Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
