GitHub user ijokarumawak opened a pull request: https://github.com/apache/nifi/pull/2424
NIFI-4393: Handle database specific identifier escape characters QueryDatabaseTable and GenerateTableFetch processors were not able to use max value state as expected, if max value column was wrapped with escape characters. Due to a mis-match between computed state keys and actual keys used in the managed state. State keys computed by getStateKey method included escape characters while actual stored keys did not. Resulted querying the same dataset again and again. This commit added unwrapIdentifier method to DatabaseAdapter class to remove database specific escape characters for identifiers such as table and column names, so that max value state keys are populated correctly even if identifiers are wrapped with escape characters. This commit also added new DatabaseAdapter for MySQL, to handle MySQL specific identifier escape with back-ticks. Thank you for submitting a contribution to Apache NiFi. In order to streamline the review of the contribution we ask you to ensure the following steps have been taken: ### For all changes: - [x] Is there a JIRA ticket associated with this PR? Is it referenced in the commit message? - [x] Does your PR title start with NIFI-XXXX where XXXX is the JIRA number you are trying to resolve? Pay particular attention to the hyphen "-" character. - [x] Has your PR been rebased against the latest commit within the target branch (typically master)? - [x] Is your initial contribution a single, squashed commit? ### For code changes: - [ ] Have you ensured that the full suite of tests is executed via mvn -Pcontrib-check clean install at the root nifi folder? - [x] Have you written or updated unit tests to verify your changes? - [ ] If adding new dependencies to the code, are these dependencies licensed in a way that is compatible for inclusion under [ASF 2.0](http://www.apache.org/legal/resolved.html#category-a)? - [ ] If applicable, have you updated the LICENSE file, including the main LICENSE file under nifi-assembly? - [ ] If applicable, have you updated the NOTICE file, including the main NOTICE file found under nifi-assembly? - [ ] If adding new Properties, have you added .displayName in addition to .name (programmatic access) for each of the new properties? ### For documentation related changes: - [ ] Have you ensured that format looks appropriate for the output in which it is rendered? ### Note: Please ensure that once the PR is submitted, you check travis-ci for build issues and submit an update to your PR as soon as possible. You can merge this pull request into a Git repository by running: $ git pull https://github.com/ijokarumawak/nifi nifi-4393 Alternatively you can review and apply these changes as the patch at: https://github.com/apache/nifi/pull/2424.patch To close this pull request, make a commit to your master/trunk branch with (at least) the following in the commit message: This closes #2424 ---- commit 93fbb976a246a75aaa6206fdafe68c6ba3ed571a Author: Koji Kawamura <ijokarumawak@...> Date: 2018-01-23T06:15:36Z NIFI-4393: Handle database specific identifier escape characters QueryDatabaseTable and GenerateTableFetch processors were not able to use max value state as expected, if max value column was wrapped with escape characters. Due to a mis-match between computed state keys and actual keys used in the managed state. State keys computed by getStateKey method included escape characters while actual stored keys did not. Resulted querying the same dataset again and again. This commit added unwrapIdentifier method to DatabaseAdapter class to remove database specific escape characters for identifiers such as table and column names, so that max value state keys are populated correctly even if identifiers are wrapped with escape characters. This commit also added new DatabaseAdapter for MySQL, to handle MySQL specific identifier escape with back-ticks. ---- ---