[BACKLOG-11838] Data Service AVG() aggregates are rounded down

[mkambol]

For TYPE_INTEGER fields, the avg calculation will truncate any
decimals. Most databases will implicitly convert to double in such
cases. This change alters the type of integer fields used in an
avg aggregation to TYPE_NUMBER prior to the in-memory group by.

http://jira.pentaho.com/browse/BACKLOG-11838
(cherry picked from commit 5291f66)

@kcruzada

[wingman-pentaho]

Build Completed

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Build Commands

mvn -B -fn -DrunITs=true -f pom.xml clean install && mvn -B -f pom.xml site

Cleanup Commands

mvn -B -f pom.xml build-helper:remove-project-artifact

Changed files

  src/main/java/org/pentaho/di/trans/dataservice/SqlTransGenerator.java
  src/test/java/org/pentaho/di/trans/dataservice/SqlTransGeneratorTest.java

Unit test coverage change

These statistics help you identify how your changes have affected the coverage of the following files. If a file is not in this list, then its coverage was not affected by your changes. To get some help interpreting these metrics, please refer to Jacoco's documentation.

org.pentaho.di.trans.dataservice.SqlTransGenerator

• Branch Change: + .36%
• Complexity Change: + 2.51%
• Instruction Change: + .52%
• Line Change: + .74%
• Method Change: + 3.88%