Summary:
This is a basic take on planning distributed writes. Main logic is in handling
the Accumulate operator, which requires Synchronize operation if the results
are used after modification.
Tests for planning distributed writes have been added.
Reviewers: florijan, msantl
Reviewed By: msantl
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1172
Summary:
With the added support for serialization, we should be able to transfer
plans across distributed workers.
The planner tests has been extended to test serialization. Operators
should be mostly tested, but the expression they contain aren't
completely. The quick solution is to use typeid for rudimentary
expression equality testing. The more involved solution of comparing
the expression tree for equality is the correct choice. It should be
done in the near future.
Reviewers: florijan, msantl
Reviewed By: florijan
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1122
Summary:
GraphDb is refactored to become an API exposing different parts
necessary for the database to function. These different parts can have
different implementations in SingleNode or distributed Master/Server
GraphDb implementations.
Interally GraphDb is implemented using two class heirarchies. One
contains all the members and correct wiring for each situation. The
other takes care of initialization and shutdown. This architecture is
practical because it can guarantee that the initialization of the
object structure is complete, before initializing state.
Reviewers: buda, mislav.bradac, dgleich, teon.banek
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1093
Summary:
Union query combinator implementation consists of:
* adjustments to the AST and `cypher_main_visitor`
* enabling `QueryStripper` to parse multiple `return` statements (not stopping after first)
* symbol generation for union results
* union logical operator
* query plan generator adjustments
Reviewers: teon.banek, mislav.bradac
Reviewed By: teon.banek
Subscribers: pullbot, buda
Differential Revision: https://phabricator.memgraph.io/D1038
Summary:
This change generates multiple PropertyFilters for expressions such as
`n.prop1 = m.prop2`. When choosing one PropertyFilter, we want to also
remove the other one, because they represent the same original
expression. Therefore, the removal is no longer based on FilterInfo
equality, but on the original expression equality. Additionally,
FilterInfo and PropertyFilter equality operators have been removed to
avoid any pretense they do what you expect or want.
Reviewers: florijan, msantl
Reviewed By: florijan
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1021
Summary:
Referring to the TCK failure on:
```
MATCH (a {name: 'Andres'})<-[:FATHER]-(child)
RETURN {foo: a.name='Andres', kids: collect(child.name)}
```
In the planner we'd only treat a list|map as a group_by if it contained
no aggregations. That's changed so that if a map contains both aggregations
and non-aggregations, then non-aggregations are treated as individual
group_by expressions.
Reviewers: teon.banek
Reviewed By: teon.banek
Subscribers: buda, pullbot, teon.banek
Differential Revision: https://phabricator.memgraph.io/D1004
Summary:
Previously, named path symbols remained untracked as `new_symbols` during planning. This meant that
operator `Optional` would be left unaware of those symbols, and therefore not reset them to `Null`
if optional matching failed.
Test Optional operator will be aware of path symbols
Reviewers: florijan, mislav.bradac
Reviewed By: mislav.bradac
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D974
Summary:
Remove name from GraphDb.
Take GraphDb in query test macros instead of accessor.
Add is_accepting_transactions flag to GraphDb.
Reviewers: mislav.bradac, florijan, mferencevic
Reviewed By: mislav.bradac
Subscribers: mferencevic, pullbot
Differential Revision: https://phabricator.memgraph.io/D940
Summary:
Move QueryParts and Filters to a new file.
Reorganize FilterInfo struct.
Remove label filter if we do indexed scan by label.
Remove property filter used in indexed scan.
Reviewers: florijan
Reviewed By: florijan
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D915
Summary: This change increases the planning time, but should reduce memory consumption.
Reviewers: florijan, mislav.bradac
Reviewed By: mislav.bradac
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D901
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:
Test planner splits MATCH ... WHERE
Remove distinction between FilterAnd and AndOperator
Reviewers: florijan, mislav.bradac
Reviewed By: mislav.bradac
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D814
Summary:
Antlr grammar has been updated to support putting edge types after the BFS
symbol. Planner collects edge type filters for BFS and inlines them in the
operator by joining the filter with the user input BFS filter itself. This
requires no change from the standpoint of the operator. On the other hand, in
order to use the faster lookup by a single edge type, `ExpandBreadthFirst`
operator now accept an optional edge type. The edge type is passed from the
planner only if the user is filtering by a single type.
Unit tests as well as tck have been updated.
Reviewers: florijan, mislav.bradac
Reviewed By: florijan
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D777
Summary: Not strictly neccessary, but it's been itching me. It took an hour.
Reviewers: buda, mislav.bradac
Reviewed By: mislav.bradac
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D648
Summary:
`UNWIND` can come before `MATCH`, so it needs to break query parts. If
it didn't, a query part would incorrectly grab all the matches and plan
them incorrectly. A test for such a case has been added.
Reviewers: florijan
Reviewed By: florijan
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D598
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:
Add optional bounds to PropertyFilter and collect them
Relation operators (e.g. `<`, `>` ...) should be used to produce
scanning the index by a range of values. For that reason, PropertyFilter
is extended to store either the equality expression or range bounds.
The `AnalyzeFilter` function is extended to look for those operators and
see if their top level expression contains a property lookup. If it
does, a filter with a bound is generated.
Test for property comparison preventing index use
Reviewers: florijan, mislav.bradac, buda
Reviewed By: florijan
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D529
Summary:
There was only two files in dbms directory so I moved them to database
directory.
Reviewers: buda
Reviewed By: buda
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D540
Summary:
Add Filters class for storing additional info
Add FindOr to utils/algorithm.hpp
Use all collected labels when scanning by them
Collect label filters inside WHERE
Document the Filters class
Reviewers: florijan, mislav.bradac, buda
Reviewed By: florijan
Subscribers: pullbot, lion
Differential Revision: https://phabricator.memgraph.io/D515
Summary:
This fixes an issue when aggregations and/or group by expressions
weren't picked up from certain operators. In addition to that, we would
segfault in cases when the `has_aggregation_` is empty. For example,
function calls without arguments: `RETURN PI()`.
Test aggregations inside some operators
Reviewers: florijan, mislav.bradac, buda
Reviewed By: mislav.bradac
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D425
Summary:
This change modifies the planning API to be more general, in order to support
picking different planning strategies. The current planning strategy has been
named RuleBasedPlanner.
Reviewers: florijan, mislav.bradac
Reviewed By: florijan
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D411
Summary:
Mention the non-existent function name in semantic error. Don't merge optional
matches into one Matching, because it is an error to treat multiple optional
matches as a single optional match. Document new structures and functions. Add
not so smart ScanAllByLabel generation.
Reviewers: mislav.bradac, buda, florijan, lion
Reviewed By: mislav.bradac
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D394
Summary:
Merge utils/visitor directory into single file.
Rename Visitor to HierarchicalVisitor.
Add regular Visitor.
Split HierarchicalVisitor into LeafVisitor and CompositeVisitor.
Add more documentation on visitor pattern.
Make PostVisit and Visit return bool.
Reviewers: florijan, mislav.bradac, buda
Reviewed By: mislav.bradac
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D364
Summary:
Make Symbol members read only.
Check WITH/RETURN * in SymbolGenerator.
Test semantic checks for WITH/RETURN *.
Sort expanded user identifiers by name.
Test planning WITH/RETURN *.
Reviewers: buda, florijan, mislav.bradac
Reviewed By: florijan
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D357
Summary:
Check symbols in property maps after visiting Match.
Plan Filters as soon as possible.
Take AstTreeStorage in MakeLogicalPlan instead of Query.
Plan generic Filter instead of specialized operators.
Remove traces of EdgeFilter and NodeFilter.
Reviewers: buda, mislav.bradac, florijan
Reviewed By: mislav.bradac, florijan
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D344
