is_value_compatible_with_internal and update_user_type were generalized
to the non-frozen case.
For now, all user_type_impls in the code are non-multi-cell (frozen).
This will be changed in future commits.
These functions are used to translate field indices, which are used to
identify fields inside UDTs, from/to a serialized representation to be
stored inside sstables and mutations.
They do it in a way that is compatible with C*.
The purpose of collection_type_impl::to_value was to serialize a
collection for sending over CQL. The corresponding function in origin
is called serializeForNativeProtocol, but the name is a bit lengthy,
so I settled for serialize_for_cql.
The method now became a free-standing function, using the visit
function to perform a dispatch on the collection type instead
of a virtual call. This also makes it easier to generalize it to UDTs
in future commits.
Remove the old serialize_for_native_protocol with a FIXME: implement
inside. It was already implemented (to_value), just called differently.
remove dead methods: enforce_limit and serialized_values. The
corresponding methods in C* are auxiliary methods used inside
serializeForNativeProtocol. In our case, the entire algorithm
is wholly written in serialize_for_cql.
`collection_type_impl::serialize_mutation_form`
became `collection_mutation(_view)_description::serialize`.
Previously callers had to cast their data_type down to collection_type
to use serialize_mutation_form. Now it's done inside `serialize`.
In the future `serialize` will be generalized to handle UDTs.
`collection_type_impl::deserialize_mutation_form`
became a free standing function `deserialize_collection_mutation`
with similiar benefits. Actually, noone needs to call this function
manually because of the next paragraph.
A common pattern consisting of linearizing data inside a `collection_mutation_view`
followed by calling `deserialize_mutation_form` has been abstracted out
as a `with_deserialized` method inside collection_mutation_view.
serialize_mutation_form_only_live was removed,
because it hadn't been used anywhere.
collection_type_impl::mutation became collection_mutation_description.
collection_type_impl::mutation_view became collection_mutation_view_description.
These classes now reside inside collection_mutation.hh.
Additional documentation has been written for these classes.
Related function implementations were moved to collection_mutation.cc.
This makes it easier to generalize these classes to non-frozen UDTs in future commits.
The new names (together with documentation) better describe their purpose.
The classes 'collection_mutation' and 'collection_mutation_view'
were moved to a separate header, collection_mutation.hh.
Implementations of functions that operate on these classes,
including some methods of collection_type_impl, were moved
to a separate compilation unit, collection_mutation.cc.
This makes it easier to modify these structures in future commits
in order to generalize them for non-frozen User Defined Types.
Some additional documentation has been written for collection_mutation.
Multi-cell lists and maps may be stored in different formats: as sorted
vectors of pairs of values, when retreived from storage, or as sorted
vectors of values, when created from parser literals or supplied as
parameter values.
Implement a specialized compare for use when receiver and paramter
representation don't match.
Add helpers.
In the system.types table a user type refers to another by name. When
a user type is modified, only its entry in the table is changed.
At runtime a user type has direct pointer to the types it uses. To
handle the discrepancy we need to recreate any dependent types when a
entry in system.types changes.
Fixes#5049
Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
They are somewhat expensive (in code size at least) and not needed
everywhere.
Inside the getter the variables are 'const data_type&', so we can
return that. Everything still works when a copy is needed, but in code
that just wants to check a property we avoid the copy.
Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
The type walking is similar to what the find function does, but
refactoring it doesn't seem worth it if these are the only two uses.
Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
The type hierarchy is closed, so we can give each leaf an enum value.
This will be used to implement a visitor pattern and reduce code
duplication.
Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
The new collector parameter is a pointer to a
`compaction_garbage_collector` implementation. This collector is passed
all atoms that are expired and would be discarded. The body of
`compact_and_expire()` was changed so that it checks cells' tombstone
coverage before it checks their expiry, so that cells that are both
covered by a tombstone and also expired are not passed to the collector.
The collector param is optional and defaults to nullptr. To accommodate
the collector, which needs to know the column id, a new `column_id`
parameter was added as well.
This is quick fix to the immediate problem of large collections causing
large allocations, triggering stalls or OOM. The proper fix is to
use IMR for storing the cells, but that is a complex change that will
require time, so let's not stall/OOM in the meanwhile.
Currently to_string takes raw bytes. This means that to print a
data_value it has to first be serialized to be passed to to_string,
which will then deserializes it.
This patch adds a virtual to_string_impl that takes a data_value and
implements a now non virtual to_sting on top of it.
I don't expect this to have a performance impact. It mostly documents
how to access a data_value without converting it to bytes.
Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
Message-Id: <20190620183449.64779-3-espindola@scylladb.com>
The to_json_string utility implementation was based on const references
instead of views, which can be a source of unnecessary memory copying.
This patch migrates all to_json_string to use bytes_view and leaves
the const reference version as a thin wrapper.
Message-Id: <2bf9f1951b862f8e8a2211cb4e83852e7ac70c67.1559654014.git.sarna@scylladb.com>