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Mike Bayer
6930dfc032
This patch replaces the ORM execution flow with a single pathway through Session.execute() for all queries, including Core and ORM. Currently included is full support for ORM Query, Query.from_statement(), select(), as well as the baked query and horizontal shard systems. Initial changes have also been made to the dogpile caching example, which like baked query makes use of a new ORM-specific execution hook that replaces the use of both QueryEvents.before_compile() as well as Query._execute_and_instances() as the central ORM interception hooks. select() and Query() constructs alike can be passed to Session.execute() where they will return ORM results in a Results object. This API is currently used internally by Query. Full support for Session.execute()->results to behave in a fully 2.0 fashion will be in later changesets. bulk update/delete with ORM support will also be delivered via the update() and delete() constructs, however these have not yet been adapted to the new system and may follow in a subsequent update. Performance is also beginning to lag as of this commit and some previous ones. It is hoped that a few central functions such as the coercions functions can be rewritten in C to re-gain performance. Additionally, query caching is now available and some subsequent patches will attempt to cache more of the per-execution work from the ORM layer, e.g. column getters and adapters. This patch also contains initial "turn on" of the caching system enginewide via the query_cache_size parameter to create_engine(). Still defaulting at zero for "no caching". The caching system still needs adjustments in order to gain adequate performance. Change-Id: I047a7ebb26aa85dc01f6789fac2bff561dcd555d