Update Opendistro 1.8 releaes notes

release-notes/opendistro-elasticsearch-sql.release-notes-0.7.0.md

@@ -0,0 +1,27 @@
+## 2019-03-11, Version 0.7.0
+
+### Notable Changes
+
+In this release, the following features are added with many other minor improvements and bug fixes.
+
+* **SQL HAVING**:
+  * Add support for SQL HAVING to filter aggregated result after GROUP BY.
+* **SQL Functions**:
+  * Common math functions as well as date function are available.
+* **Nested Field Query**:
+  * Query nested field in SQL++ syntax instead of explicit nested() function.
+* **JSON in RESTful Request**:
+  * Support JSON payload to allow for ESRally benchmark and parameters in JDBC request. And also pretty format and flatten native Elasticsearch DSL as response.
+* **Block Hash Join**:
+  * Introduced new query planning framework and new hash join algorithm with memory protection mechanism to perform hash join block by block safely.
+
+
+### Major Refactoring & Architecture Changes
+
+* **Avoid I/O Operation in NIO Thread**
+  * Move I/O blocking operations to custom worker thread pool or prefetch to avoid blocking. Meanwhile non-blocking operations still run in Elasticsearch transport thread for efficiency.
+
+
+### Commits
+
+* [[`56dd269`](https://github.com/mauve-hedgehog/opendistro-elasticsearch-sql/commit/56dd269871259dae9fb77ab512005b9a714d728e)] Initial commit

release-notes/opendistro-elasticsearch-sql.release-notes-0.8.0.md

@@ -0,0 +1,7 @@
+## 2019-04-02, Version 0.8.0
+
+### Notable Changes
+
+* Feature [#12](https://github.com/opendistro-for-elasticsearch/sql/issues/12): Add support for Elasticsearch 6.6.2
+* Bug fix [#9](https://github.com/opendistro-for-elasticsearch/sql/issues/9): Fix issue for query by index pattern in JDBC driver.
+* Bug fix [#10](https://github.com/opendistro-for-elasticsearch/sql/issues/10): Return friendly error message instead of NPE for illegal query and other exception cases.

release-notes/opendistro-elasticsearch-sql.release-notes-0.9.0.md

@@ -0,0 +1,6 @@
+## 2019-04-19, Version 0.9.0
+
+### Notable Changes
+
+* Feature [#29](https://github.com/opendistro-for-elasticsearch/sql/issues/29): Add support for Elasticsearch 6.7.1
+* Migration [#17](https://github.com/opendistro-for-elasticsearch/sql/issues/17): Migrate legacy integration tests in Maven to ES test in Gradle.

release-notes/opendistro-elasticsearch-sql.release-notes-1.0.0.md

@@ -0,0 +1,11 @@
+## 2019-06-10, Version 1.0.0
+
+### Notable Changes
+
+* Feature [#47](https://github.com/opendistro-for-elasticsearch/sql/issues/47): Support for Elasticsearch 7.0.1.
+* Feature [#56](https://github.com/opendistro-for-elasticsearch/sql/issues/56): Adding coverage report.
+* Feature [#65](https://github.com/opendistro-for-elasticsearch/sql/issues/65): Support for enabling/disabling SQL feature.
+
+* BugFix [#44](https://github.com/opendistro-for-elasticsearch/sql/issues/44): Fixing the order of fields in csv output
+* BugFix [#68](https://github.com/opendistro-for-elasticsearch/sql/issues/68): Support number field
+* BugFix [#37](https://github.com/opendistro-for-elasticsearch/sql/issues/37): Fix for PERCENTILES query result in csv output

release-notes/opendistro-elasticsearch-sql.release-notes-1.1.0.md

@@ -0,0 +1,11 @@
+## 2019-06-21, Version 1.1.0
+
+### Notable Changes
+
+* Feature [#90](https://github.com/opendistro-for-elasticsearch/sql/issues/90): Elasticsearch 7.1.1 compatibility
+* Migration [#17](https://github.com/opendistro-for-elasticsearch/sql/issues/17): Finished integ test migration and deprecated Maven build.
+* Enhancement [#34](https://github.com/opendistro-for-elasticsearch/sql/issues/34): Detached request ID from SqlRequest object.
+
+* BugFix [#46](https://github.com/opendistro-for-elasticsearch/sql/issues/46): Multi-index queries require identical mappings for indices.
+* BugFix [#92](https://github.com/opendistro-for-elasticsearch/sql/issues/92): Improper handling of SELECT statement
+* BugFix [#93](https://github.com/opendistro-for-elasticsearch/sql/issues/93): Blank query causes IndexOutOfBoundsException

release-notes/opendistro-elasticsearch-sql.release-notes-1.2.0.md

@@ -0,0 +1,13 @@
+## 2019-07-23, Version 1.2.0
+
+### Notable changes
+
+* Feature [#125](https://github.com/opendistro-for-elasticsearch/sql/issues/125): Elasticsearch 7.2.0 compatibility
+* Feature [#103](https://github.com/opendistro-for-elasticsearch/sql/issues/103): Sort on custom script based functions 
+
+* BugFix [#104](https://github.com/opendistro-for-elasticsearch/sql/issues/104): GROUP BY and ORDER BY for custom script based functions 
+generated wrong DSL
+* BugFix [#95](https://github.com/opendistro-for-elasticsearch/sql/issues/95): NPE thrown when selecting all in query with nested fields involved
+* BugFix [#108](https://github.com/opendistro-for-elasticsearch/sql/issues/108): Custom script based functions weren't supported in JDBC
+
+and other minor bugfixes

release-notes/opendistro-elasticsearch-sql.release-notes-1.2.1.md

@@ -0,0 +1,5 @@
+## 2019-10-15, Version 1.2.1
+
+### Notable changes
+
+* Feature [#202](https://github.com/opendistro-for-elasticsearch/sql/issues/202): Elasticsearch 7.2.1 compatibility

release-notes/opendistro-elasticsearch-sql.release-notes-1.3.0.md

@@ -0,0 +1,39 @@
+## 2019-10-29, Version 1.3.0
+
+### Notable changes
+
+* Feature [#258](https://github.com/opendistro-for-elasticsearch/sql/issues/185): Elasticsearch 7.3.2 compatibility
+* Feature [#201](https://github.com/opendistro-for-elasticsearch/sql/pull/201): Improve query verification by adding semantic analyzer
+
+* Enhancement [#262](https://github.com/opendistro-for-elasticsearch/sql/pull/262): Support CASE statement in one more grammer
+* Enhancement [#253](https://github.com/opendistro-for-elasticsearch/sql/pull/253): Support Cast function
+* Enhancement [#260](https://github.com/opendistro-for-elasticsearch/sql/pull/260): Support string operators: ASCII, RTRIM, LTRIM, LOCATE, LENGTH, REPLACE
+* Enhancement [#254](https://github.com/opendistro-for-elasticsearch/sql/issues/254): Support SELECT <number_literal>
+* Enhancement [#251](https://github.com/opendistro-for-elasticsearch/sql/pull/251): Support number operators: POWER, ATAN2, COT, SIGN/SIGNUM
+* Enhancement [#215](https://github.com/opendistro-for-elasticsearch/sql/issues215): Support ordinal in GROUP/ORDER BY clause
+* Enhancement [#213](https://github.com/opendistro-for-elasticsearch/sql/issues/213): Support `<table>.<column>` syntax
+* Enhancement [#212](https://github.com/opendistro-for-elasticsearch/sql/issues/212): Support Quoted identifiers
+* Enhancement [#199](https://github.com/opendistro-for-elasticsearch/sql/issues/199): Support NOT operator with nested field query
+* Enhancement [#166](https://github.com/opendistro-for-elasticsearch/sql/issues/166): Support pretty option for explain request
+* Enhancement [#162](https://github.com/opendistro-for-elasticsearch/sql/issues/162): Support ORDER BY for 2 or more columns sorts only by last column in aggregation query
+* Enhancement [#151](https://github.com/opendistro-for-elasticsearch/sql/issues/151): Improve query verification and exception handling
+* Enhancement [#128](https://github.com/opendistro-for-elasticsearch/sql/issues/128): Support case-changing functions
+* Enhancement [#120](https://github.com/opendistro-for-elasticsearch/sql/issues/120): Support aggregation function in HAVING
+* Enhancement [#82](https://github.com/opendistro-for-elasticsearch/sql/issues/82): Pre-verification before actual execution of query
+* Enhancement [#75](https://github.com/opendistro-for-elasticsearch/sql/issues/75): Support order by on SQL functions like SUM etc
+
+* BugFix [#265](https://github.com/opendistro-for-elasticsearch/sql/pull/265): Fix the LOG function that delivered inaccurate result
+* BugFix [#233](https://github.com/opendistro-for-elasticsearch/sql/issues/233): Function names are case-sensitive
+* BugFix [#191](https://github.com/opendistro-for-elasticsearch/sql/issues/191): Fix new syntax check for LEFT JOIN on nested field and metadata field
+* BugFix [#188](https://github.com/opendistro-for-elasticsearch/sql/issues/188): Having doesn't working on nested field
+* BugFix [#187](https://github.com/opendistro-for-elasticsearch/sql/issues/187): Aggregation on Nested Array Field return unexpected value
+* BugFix [#186](https://github.com/opendistro-for-elasticsearch/sql/issues/186): Alias of group key is not returned correctly
+* BugFix [#176](https://github.com/opendistro-for-elasticsearch/sql/issues/176): ORDER BY expects function names written only in lowercase
+* BugFix [#175](https://github.com/opendistro-for-elasticsearch/sql/issues/175): ORDER BY doesn't respect table aliases
+* BugFix [#170](https://github.com/opendistro-for-elasticsearch/sql/issues/170): Some flaky test cases fail and pass after retry
+* BugFix [#158](https://github.com/opendistro-for-elasticsearch/sql/issues/158): Aliases aren't working for ORDER BY and GROUP BY
+* BugFix [#132](https://github.com/opendistro-for-elasticsearch/sql/issues/132): Integration Test Cluster doesn't terminated when integration test failed
+* BugFix [#125](https://github.com/opendistro-for-elasticsearch/sql/issues/125): Parsing Exception when WHERE clause has true/false in CONDITION
+* BugFix [#122](https://github.com/opendistro-for-elasticsearch/sql/issues/122): Query with custom-function doesn't respect LIMIT
+* BugFix [#121](https://github.com/opendistro-for-elasticsearch/sql/issues/121): Dot/period at start of index name fails to parse
+* BugFix [#111](https://github.com/opendistro-for-elasticsearch/sql/issues/111): JDBC format of aggregation query with date_format adds unnecessary column bug

release-notes/opendistro-elasticsearch-sql.release-notes-1.4.0.md

@@ -0,0 +1,40 @@
+## 2020-01-24, Version 1.4.0
+
+### Features
+#### Elasticsearch Compatibility
+* Feature [#312](https://github.com/opendistro-for-elasticsearch/sql/issues/312): Elasticsearch 7.4.2 compatibility 
+
+#### Testing
+* Feature ([#335](https://github.com/opendistro-for-elasticsearch/sql/pull/335), [#343](https://github.com/opendistro-for-elasticsearch/sql/pull/343)): Sql test bench bug fix, improvement and more test cases (issues: [#335](https://github.com/opendistro-for-elasticsearch/sql/issues/335), [#339](https://github.com/opendistro-for-elasticsearch/sql/issues/339))
+
+#### Documentation
+* Feature ([#302](https://github.com/opendistro-for-elasticsearch/sql/pull/302), [#305](https://github.com/opendistro-for-elasticsearch/sql/pull/305), [#303](https://github.com/opendistro-for-elasticsearch/sql/pull/303)): Documentation for basic usage of plugin & improvement of contributing docs (issues: [#293](https://github.com/opendistro-for-elasticsearch/sql/issues/293), [#243](https://github.com/opendistro-for-elasticsearch/sql/issues/243))
+
+#### Github Actions
+* Feature ([#283](https://github.com/opendistro-for-elasticsearch/sql/pull/283), [#287](https://github.com/opendistro-for-elasticsearch/sql/pull/287)): Added github action to build and run tests. Gradle build will publish compiled plugin, that is ready to install into elastic
+
+### Enhancements
+#### Lexer and Semantic
+* Enhancement [#345](https://github.com/opendistro-for-elasticsearch/sql/pull/345): Syntax and semantic exceptions handling for unsupported features (issue: [#320](https://github.com/opendistro-for-elasticsearch/sql/issues/320))
+
+#### SQL Feature
+* Enhancement ([#346](https://github.com/opendistro-for-elasticsearch/sql/pull/346), [#352](https://github.com/opendistro-for-elasticsearch/sql/pull/352)): Support function over aggregation result (issues: [#194](https://github.com/opendistro-for-elasticsearch/sql/issues/194), [#229](https://github.com/opendistro-for-elasticsearch/sql/issues/229), [#270](https://github.com/opendistro-for-elasticsearch/sql/issues/270), [#292](https://github.com/opendistro-for-elasticsearch/sql/issues/292))
+* Enhancement [#273](https://github.com/opendistro-for-elasticsearch/sql/pull/273): Support conditional functions: IF, IFNULL, ISNULL (issues: [#224](https://github.com/opendistro-for-elasticsearch/sql/issues/224), [#235](https://github.com/opendistro-for-elasticsearch/sql/issues/235)) 
+* Enhancement [#274](https://github.com/opendistro-for-elasticsearch/sql/pull/274): Support JOIN without table alias (issue: [#232](https://github.com/opendistro-for-elasticsearch/sql/issues/232))
+* Enhancement [#278](https://github.com/opendistro-for-elasticsearch/sql/pull/278): Support subquery in from with parent only has select (issue: [#230](https://github.com/opendistro-for-elasticsearch/sql/issues/230))
+* Enhancement [#282](https://github.com/opendistro-for-elasticsearch/sql/pull/282): Support datetime functions: MONTH, DAYOFMONTH, DATE, MONTHNAME, TIMESTAMP, MAKETIME, NOW, CURDATE (issue: [#235](https://github.com/opendistro-for-elasticsearch/sql/issues/235))
+* Enhancement [#300](https://github.com/opendistro-for-elasticsearch/sql/pull/300): Support DISTINCT feature in SELECT clause (issue: [#294](https://github.com/opendistro-for-elasticsearch/sql/issues/294))
+
+#### Response
+* Enhancement [#334](https://github.com/opendistro-for-elasticsearch/sql/pull/334): Change the default response format to JDBC (issue: [#159](https://github.com/opendistro-for-elasticsearch/sql/issues/159))
+
+### Bugfixes
+* BugFix [#267](https://github.com/opendistro-for-elasticsearch/sql/pull/267): Fixed operatorReplace Integration Test (issue: [#266](https://github.com/opendistro-for-elasticsearch/sql/issues/266))
+* BugFix [#275](https://github.com/opendistro-for-elasticsearch/sql/pull/275): Fix issue that IP type cannot pass JDBC formatter (issue: [#272](https://github.com/opendistro-for-elasticsearch/sql/issues/272))
+* BugFix [#284](https://github.com/opendistro-for-elasticsearch/sql/pull/284): Fixed flaky test suite, that was breaking Github action build
+* BugFix [#295](https://github.com/opendistro-for-elasticsearch/sql/pull/295): Corrected the selected field names displayed in the schema of JDBC formatted response (issue: [#290](https://github.com/opendistro-for-elasticsearch/sql/issues/290))
+* BugFix [#296](https://github.com/opendistro-for-elasticsearch/sql/pull/296): Fixed functions work improperly with fieldvalue/constant param for current use (issues: [#279](https://github.com/opendistro-for-elasticsearch/sql/issues/279), [#291](https://github.com/opendistro-for-elasticsearch/sql/issues/291), [#224](https://github.com/opendistro-for-elasticsearch/sql/issues/224))
+* BugFix [#298](https://github.com/opendistro-for-elasticsearch/sql/pull/298): Fixed issue of log10 function gets inaccurate results （issue: [#297](https://github.com/opendistro-for-elasticsearch/sql/issues/297))
+* BugFix [#307](https://github.com/opendistro-for-elasticsearch/sql/pull/307): Fix the issue of column alias not working for GROUP BY (issue: [#299](https://github.com/opendistro-for-elasticsearch/sql/issues/299))
+* BugFix [#333](https://github.com/opendistro-for-elasticsearch/sql/pull/333): Fixed the issue of substring not working correctly when fieldname is put as <table>.<column> (issue: [#330](https://github.com/opendistro-for-elasticsearch/sql/issues/330))
+* BugFix [#337](https://github.com/opendistro-for-elasticsearch/sql/pull/337): Fix JDBC response for delete query (issue: [#131](https://github.com/opendistro-for-elasticsearch/sql/issues/131))

release-notes/opendistro-elasticsearch-sql.release-notes-1.6.0.md

@@ -0,0 +1,27 @@
+## 2020-03-24 Version 1.6.0.0
+
+### Features
+#### Elasticsearch Compatibility
+* Feature [#376](https://github.com/opendistro-for-elasticsearch/sql/issues/376): Elasticsearch 7.6.1 compatibility
+
+#### Testing
+* Feature [#374](https://github.com/opendistro-for-elasticsearch/sql/pull/374): Integration test with external ES cluster (issue: [353](https://github.com/opendistro-for-elasticsearch/sql/issues/353))
+* Feature [#384](https://github.com/opendistro-for-elasticsearch/sql/pull/384): CI/CD using github Actions workflow
+
+#### Documentation
+* Feature [#366](https://github.com/opendistro-for-elasticsearch/sql/pull/366): Documentation for simple query (issue: [#363](https://github.com/opendistro-for-elasticsearch/sql/issues/363)) 
+* Feature [#379](https://github.com/opendistro-for-elasticsearch/sql/pull/379): Documentation for Pagination (issue: [#16](https://github.com/opendistro-for-elasticsearch/sql/issues/16))
+
+### Enhancements
+#### SQL Features
+* Enhancement [#367](https://github.com/opendistro-for-elasticsearch/sql/pull/367): Report date data as a standardized format (issue: [#342](https://github.com/opendistro-for-elasticsearch/sql/issues/342))
+
+#### Exception Handling
+* Enhancement [#362](https://github.com/opendistro-for-elasticsearch/sql/pull/362): Handle the elasticsearch exceptions in JDBC formatted outputs(issues: [#320](https://github.com/opendistro-for-elasticsearch/sql/issues/320), [308](https://github.com/opendistro-for-elasticsearch/sql/issues/308))
+* Enhancement [#372](https://github.com/opendistro-for-elasticsearch/sql/pull/372): Modified the wording of exception messages and created the troubleshooting page(issue: [#320](https://github.com/opendistro-for-elasticsearch/sql/issues/320))
+
+### Bugfixes
+* Bugfix [#310](https://github.com/opendistro-for-elasticsearch/sql/pull/310): Add DATETIME cast support (issue: [#268](https://github.com/opendistro-for-elasticsearch/sql/issues/268))
+* BugFix [#365](https://github.com/opendistro-for-elasticsearch/sql/pull/365): Return Correct Type Information for Fields (issue: [#316](https://github.com/opendistro-for-elasticsearch/sql/issues/316))
+* BugFix [#377](https://github.com/opendistro-for-elasticsearch/sql/pull/377): Return object type for field which has implicit object datatype when describe the table (issue:[sql-jdbc#57](https://github.com/opendistro-for-elasticsearch/sql-jdbc/issues/57))
+* BugFix [#381](https://github.com/opendistro-for-elasticsearch/sql/pull/381): FIX field function name letter case preserved in select with group by (issue: [#373](https://github.com/opendistro-for-elasticsearch/sql/issues/373))

release-notes/opendistro-elasticsearch-sql.release-notes-1.7.0.md

@@ -0,0 +1,24 @@
+## 2020-05-04 Version 1.7.0.0
+
+#### Breaking Changes
+* Change [#414](https://github.com/opendistro-for-elasticsearch/sql/pull/414): Invalidate HTTP GET method.
+
+### Features
+#### SQL Features
+* Feature [#390](https://github.com/opendistro-for-elasticsearch/sql/pull/390): Simple Query Cursor support. (issue: [#16](https://github.com/opendistro-for-elasticsearch/sql/issues/16))
+* Feature [#400](https://github.com/opendistro-for-elasticsearch/sql/pull/400): New SQL cluster settings endpoint.
+#### Documentation
+* Feature [#417](https://github.com/opendistro-for-elasticsearch/sql/pull/417): More docs in reference manual and add architecture doc. (issue: [#380](https://github.com/opendistro-for-elasticsearch/sql/issues/380)) 
+#### Security
+* Change [#456](https://github.com/opendistro-for-elasticsearch/sql/pull/456): Escape comma for CSV header and all queries. (issue: [#455](https://github.com/opendistro-for-elasticsearch/sql/issues/455))
+* Change [#447](https://github.com/opendistro-for-elasticsearch/sql/pull/447): Fix CSV injection issue. (issue: [#449](https://github.com/opendistro-for-elasticsearch/sql/issues/449))
+* Change [#419](https://github.com/opendistro-for-elasticsearch/sql/pull/419): Anonymize sensitive data in queries exposed to RestSqlAction logs. (issue: [#97](https://github.com/opendistro-for-elasticsearch/sql/issues/97))
+
+### Bugfixes
+* Bugfix [#452](https://github.com/opendistro-for-elasticsearch/sql/pull/452): Support using aggregation function in order by clause. (issue: [#277](https://github.com/opendistro-for-elasticsearch/sql/issues/277))
+* Bugfix [#442](https://github.com/opendistro-for-elasticsearch/sql/pull/442): Count(distinct field) should translate to cardinality aggregation. (issue: [#439](https://github.com/opendistro-for-elasticsearch/sql/issues/439))
+* Bugfix [#437](https://github.com/opendistro-for-elasticsearch/sql/pull/437): Enforce AVG return double data type. (issue: [#408](https://github.com/opendistro-for-elasticsearch/sql/issues/408))
+* Bugfix [#425](https://github.com/opendistro-for-elasticsearch/sql/pull/425): Ignore the term query rewrite if there is no index found. (issue: [#355](https://github.com/opendistro-for-elasticsearch/sql/issues/355))
+* Bugfix [#418](https://github.com/opendistro-for-elasticsearch/sql/pull/418): Support subquery in from doesn't have alias. (issue: [#416](https://github.com/opendistro-for-elasticsearch/sql/issues/416))
+* Bugfix [#412](https://github.com/opendistro-for-elasticsearch/sql/pull/412): Add support for strict_date_optional_time. (issue: [#411](https://github.com/opendistro-for-elasticsearch/sql/issues/411))
+* Bugfix [#381](https://github.com/opendistro-for-elasticsearch/sql/pull/381): field function name letter case preserved in select with group by. (issue: [#373](https://github.com/opendistro-for-elasticsearch/sql/issues/373))