Summary: This is not a very important functionality, but it turned out simple to do, so let's add it to have a consistent query support.
Reviewers: buda, teon.banek
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D862
Summary:
- Removed BreadthFirstAtom, using EdgeAtom only with a Type enum.
- Both variable expansions (breadth and depth first) now have mandatory inner node and edge Identifiers.
- Both variable expansions use inline property filtering and support inline lambdas.
- BFS and variable expansion now have the same planning process.
- Planner modified in the following ways:
- Variable expansions support inline property filtering (two filters added to all_filters, one for inline, one for post-expand).
- Asserting against existing_edge since we don't support that anymore.
- Edge and node symbols bound after variable expansion to disallow post-expand filters to get inlined.
- Some things simplified due to different handling.
- BreadthFirstExpand logical operator merged into ExpandVariable. Two Cursor classes remain and are dynamically chosen from.
As part of planned planner refactor we should ensure that a filter is applied only once. The current implementation is very suboptimal for property filtering in variable expansions.
@buda: we will start refactoring this these days. This current planner logic is too dense and complex. It is becoming technical debt. Most of the time I spent working on this has been spent figuring the planning out, and I still needed Teon's help at times. Implementing the correct and optimal version of query execution (avoiding multiple potentially expensive filterings) was out of reach also due to tech debt.
Reviewers: buda, teon.banek
Reviewed By: teon.banek
Subscribers: pullbot, buda
Differential Revision: https://phabricator.memgraph.io/D852
Summary:
- The new BFS syntax implemented as proposed.
- AST BreadthFirstAtom now uses EdgeAtom members: has_range_{true}, upper_bound_, lower_bound_
- Edges data structure now handles all the edge filtering (single or multiple edges), to ease planning. Additional edge filtering (additional Filter op in the plan) is removed. AST EdgeTypeTest is no longer used and is removed.
Current state is stable but there are things left to do:
- BFS property filtering.
- BFS lower_bound_ support.
- Support for lambdas in variable length expansion. This includes obligatory (even if not user_defined) inner_node and inner_edge symbols for easier handling.
- Code-sharing between BFS and variable length expansions.
I'll add asana tasks (and probably start working on them immediately) when/if this lands.
Reviewers: buda, teon.banek, mislav.bradac
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D836
Summary:
- Keys() functions in the indices can't be const because ConcurrentMap doesn't provide const accessors (and they are broken in skiplist) :D
- no cucumber tests because many tests create indices so it's hard to say what's inside and what not
Reviewers: buda, mislav.bradac
Reviewed By: mislav.bradac
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D797
Summary: `assert` function added. Useful to us for asserting DB state in harness tests. Potentially useful to the client for breaking out of a query as soon as a predicate fails, as opposed to collecting result and checking them client-side.
Reviewers: buda, mislav.bradac, teon.banek
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D750
Summary:
- added only one function for getting the total (in + out) vertex degree, it's required for the Ravelin use-case
- specific `degree_in` and `degree_out` functions can be added as necessary
- also fixed random_graph_generator bug (needed it for testing)
Reviewers: buda, mislav.bradac
Reviewed By: buda, mislav.bradac
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D652
Summary:
Add All expression to Ast
Evaluate All expression
Visit All and generate symbols
Handle All when collecting context during planning
Reviewers: florijan, mislav.bradac, buda
Reviewed By: mislav.bradac
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D587
Summary:
The openCypher chapter of user documentation now includes information on
creating label & property index.
Reviewers: florijan, buda
Reviewed By: florijan
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D537
Summary:
Do some minor corrections to openCypher docs
Add links to Bolt drivers in our documentation
Reviewers: florijan, buda, mferencevic, dtomicevic
Reviewed By: buda
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D440
Summary:
This is a basic overview of various supported features of openCypher in
Memgraph. A lot of the documentation refers to Neo4j manual. This needs to
change in the future.
Reviewers: buda, dtomicevic, mislav.bradac, florijan
Reviewed By: buda
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D439
