# Changelog
All notable changes to this project will be documented in this file.

## [0.3.0] - 2016-11-08
### Added
- New operators
    - PlaceOfServiceFilter
    - Provenance
    - ProviderFilter
    - CoReported
- Support for :impala_mem_limit option
- Initial support for dynamic columns
- Additional columns for observation domains and drug domains
- Support for :within, :occurrences, :at_least

### Changed
- Format of this [CHANGELOG](http://keepachangelog.com/en/0.3.0/)
- Read searches Condition, Procedure, Drug, Observation
- Rewrote OneInTwoOut to produce faster queries
- Except operator uses different strategy under Impala

### Fixed
- Fixed date casting and other issues for Impala compatibility.
- Fixed ConditionType to accept concept_ids

## [0.2.0] - 2015-12-11
### Added
- Optimized After/Before nodes when multi-person results are in the right stream.
- Set end_date as coalesce(end_date, start_date) to make range if end_date missing.
- Nodes
    - AnyOverlap
    - Contains
    - Filter
    - Ndc
    - ObservationPeriod
    - OneInTwoOut
    - OverlappedBy
    - Overlaps
    - TrimDateEnd
    - TrimDateStart
- Nodes for CPRD
    - Medcode
    - MedcodeProcedure
    - ObservationByEnttype
    - Prodcode
- Nodes for SEER
    - FromSeerVisits
    - ToSeerVisits
- Ability to limit results to a set of patients by setting Tree#person_ids
- "units_source_value" and "source_value" columns in results
- TimeWindow supports date literals
- ConditionType supports search for "primary"
- Nodifier#to_metadata

### Changed
- Except now allows :ignore_date option
    - Comparison is only done on criterion_id/type
- DateRange START/END use observation_period instead of visit_occurrence
- Operator#columns value_as_numeric => value_as_number
- Syntax is now more "lispy"
- Recall now uses any labeled operator as if that operator was fed to "Define" operator
- Nodes now called Operators

### Removed
- Let/Define operators

### Fixed
- Many broken specs.
- Union calls #from_self on incoming streams to avoid column issues
- Concept node now works again
- Define ensures tables are built

## [0.1.1] - 2014-09-18
### Fixed
- Calling Query#sql no longer creates a bunch of temporary tables.

## [0.1.0] - 2014-09-04
### Added
- Support for numeric, string, and concept_ids returned in results.
- Many updates to the ConceptQL Specification document.
- Added doc/implementation_notes.md to capture thoughts and bad ideas.

### Fixed
- "Fake" graphs are now drawn correctly.
- bin/conceptql doesn't bomb out drawing "fake" graphs

## [0.0.9] - 2014-09-03
### Added
- Support for MSSQL (SQL Server).

### Fixed
- Removed debug output from Node#namify

## [0.0.8] - 2014-08-28
### Added
- Support for Oracle.

### Fixed
- DateAdjuster/TimeWindow use Sequel's date_arithmetic extension to produce database agnostic date manipulation.
- Breakage from Node#tree in GraphNodifier.
- All tests are back to passing.
- Changed from SHA1 to CRC32 hash since Oracle can't handle table names longer than 30 characters.

## [0.0.6] - 2014-08-23
### Added
- Support for Oracle
- Tree#defined to pass type information between Define and Recall.
- Node#sql to produce SQL for each node.
- Graph includes row count on each edge in the diagram.

### Fixed
- Bug in CastingNode that generate SQL returning multiple columns in a subquery.
- Made ruby-graphviz a dependency so calling programs don't bomb out.
- Define now passes rows on through like any other node!
- DateAdjuster/TimeWindow use Sequel's date_arithmetic extension to produce database agnostic date manipulation.
- All tests are back to passing.

## [0.0.5] - 2014-08-19
### Fixed
- Bug in GraphNodifier not displaying types for `recall` nodes.

## [0.0.4] - 2014-08-19
### Added
- Support for 5 instead of 13 column internal representation of results.
- `define` node, used to create "variables" in ConceptQL.
- `recall` node, used to pull results from "variables" in ConceptQL.

### Removed
- Support for 13 column results.
- Dependency on a set of views to run SQL queries.

### Fixed
- Bug where `place_of_service_code` wasn't limited to vocabulary_id 14

## [0.0.3] - 2014-08-12
### Added
- FakeGrapher class to make it easier to generate diagrams with experimental nodes
- fake_graph command has returned to the `conceptql` program
- GraphNodifier now supports:
    - condition_type as condition_occurrence
    - drg as procedure_occurrence
    - vsac as misc

### Fixed
- Tree now runs #deep_symbolize_keys on incoming statements

## [0.0.2] - 2014-07-11
### Removed
- Several commands from `conceptql` program
    - fake_graph
    - show_db_graph
    - show_and_tell_db

## [0.0.1] - 2014-07-11
### Added
- This project.