• NAME
• SYNOPSIS
• DESCRIPTION
• REQUIRED METHODS

NAME

KiokuDB::Backend::Role::TXN::Memory - In memory transactions.

SYNOPSIS

    with qw(KiokuDB::Backend::Role::TXN::Memory);

    sub commit_entries {
        my ( $self, @entries ) = @_;

        # atomically apply @entries

        # deleted entries have the deleted flag set
        # if an entry has no 'prev' entry it's an insert
        # otherwise it's an update
    }

DESCRIPTION

This backend provides in memory transactions for backends which support atomic modification of data, but not full commit/rollback support.

This backend works by buffering all operations in memory. Entries are kept alive allowing read operations go to the live entry even for objects that are out of scope.

This implementation provides repeatable read level isolation. Durability, concurrency and atomicity are still the responsibility of the backend.

REQUIRED METHODS

commit_entries

Insert, update or delete entries as specified.

This operation should either fail or succeed atomically.

Entries with deleted should be removed from the database, entries with a prev entry should be inserted, and all other entries should be updated.

Multiple entries may be given for a single object, for instance an object that was first inserted and then modified will have an insert entry and an update entry.

get_from_storage

Should be the same as "get" in KiokuDB::Backend.

When no memory buffered entries are available for the object one is fetched from the backend.

exists_in_storage

Required as of KiokuDB version 0.37.

A fallback implementation is provided, but should not be used and will issue a deprecation warning.