Add CHANGELOG.md file (#843)

Add CHANGELOG.md file

Author: ajnavarro

CHANGELOG.md

@@ -0,0 +1,67 @@
+# Changelog
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+## [0.20.0] - 2019-05-30
+### Known Issues
+- After updating Vitess MySQL server, we are having some problems connecting from JDBC MariaDB drivers (https://github.com/src-d/gitbase/issues/807) (https://github.com/vitessio/vitess/issues/4603) 
+
+### Added
+- function: implement is_vendor function (#830)
+- Suggest table/column/indexes names on missing errors
+- sql: HAVING clause
+- Support SHOW SCHEMAS (upgrade vitess to v1.6.0) (https://github.com/src-d/go-mysql-server/pull/696)
+- function: LOC function implementation (#798)
+- sql/expression: new DATE function
+- sql: add support for intervals, DATE_SUB and DATE_ADD
+- sql: from_base64 and to_base64 functions
+- sql: add SLEEP function
+- COUNT expression now returns an int64 number instead of int32 https://github.com/src-d/go-mysql-server/issues/642
+- Dockerfile: include zero-config MySQL client https://github.com/src-d/gitbase/pull/737
+- uast_extract function now returns a JSON for `pos` instead of a custom format https://github.com/src-d/gitbase/pull/715
+
+#### Documentation
+- docs: expand optimization guide on early filtering (#837)
+- Now all relevant go-mysql-server documentation is directly accessible from gitbase docs instead of pointing to external links.
+- Docs: document in-memory joins in optimization docs https://github.com/src-d/gitbase/pull/742
+
+#### Performance
+-  Make mapping per partition on Index creation, improving performance (https://github.com/src-d/go-mysql-server/pull/681).
+- sql/index/pilosa: parallelize index creation
+- Perf: improve the way we check if refs are not pointing to commits https://github.com/src-d/gitbase/pull/780
+- Plan: compute all inner joins in memory if they fit https://github.com/src-d/go-mysql-server/issues/577
+- Perf: Avoid call to Checksum if there are no indexes https://github.com/src-d/go-mysql-server/pull/631
+
+### Changed
+- COUNT expression is returning now int64 instead of int32
+- uast_extract function now returns a JSON for `pos` instead of a custom format
+- Now relative paths are used as repository_id instead of folder name
+
+### Fixed
+- avoid panic when there are no fetch URLs in remote config (#836)
+- upgrade go-mysql-server and gocloc (#831)
+- rule: fix squash rule with convert_dates
+- cmd/server/commands: use relative path as id instead of last part (#816)
+- handle backslashes correctly
+- sql/plan: make sure outdated indexes can be dropped
+- sql/analyzer: correctly qualify aliases with the same name as col
+- Fix validation rule to detect tuples in projections or groupbys (https://github.com/src-d/go-mysql-server/pull/672)
+- sql/analyzer: only check aliases to qualify in the topmost project (https://github.com/src-d/go-mysql-server/pull/690)
+- Fix special case for aggregation in ORDER BY
+- Try to order by function (https://github.com/src-d/go-mysql-server/pull/692)
+- Don't skip repositories for remotes table with more than 1 URL https://github.com/src-d/gitbase/pull/789
+- server: correctly set binary charset on blob fields
+- sql/parse: allow qualified table names on SHOW CREATE TABLE
+- plan: types in lowercase on SHOW CREATE TABLE
+- Skip a directory if gitbase has no permission to read it https://github.com/src-d/gitbase/pull/738
+- Close iterators correctly to avoid too many open files error https://github.com/src-d/gitbase/pull/772
+- Check projection aliases when assigned to index https://github.com/src-d/go-mysql-server/issues/639
+- Add charset to fields to avoid invalid column types when using JDBC clients https://github.com/src-d/go-mysql-server/pull/637
+- Fix prune columns for describe queries https://github.com/src-d/go-mysql-server/pull/634
+- Allow all expressions in grouping, resolve order by expressions https://github.com/src-d/go-mysql-server/pull/633
+- KILL query always takes processlist_id https://github.com/src-d/go-mysql-server/pull/636
+- Recover panic for partitions https://github.com/src-d/go-mysql-server/pull/626

pull_request_template.md

@@ -2,9 +2,10 @@
 
 All PRs must keep the documentation up to date. If this PR changes or adds some new behavior don't forget to check:
 
+- add new fix or feature to CHANGELOG.md file
 - Schema changes
 - Syntax changes
 - Add or update examples
-- `go run ./tools/rev-upgrade/main.go -p "gopkg.in/src-d/go-mysql-server.v0" [-r "revision"]`
+- make upgrade
 
  -->