Gian Merlino 82fbb31c7c

Properly read SQL-compatible segments in default-value mode. (#14142) ...

* Properly read SQL-compatible segments in default-value mode.

Main changes:

1) Dictionary-encoded and front-coded string columns: in default-value
   mode, detect cases where a dictionary has the empty string in it, then
   either combine it with null (if null is present) or replace it with
   null (if null is not present).

2) Numeric nullable columns: in default-value mode, ignore the null
   value bitmap. This causes all null numbers to be read as zeroes.

Testing strategy:

1) Add a mmappedWithSqlCompatibleNulls case to BaseFilterTest that
   writes segments under SQL-compatible mode, and reads them under
   default-value mode.

2) Unit tests for the new wrapper classes (CombineFirstTwoEntriesIndexed,
   CombineFirstTwoValuesColumnarInts, CombineFirstTwoValuesColumnarMultiInts,
   CombineFirstTwoValuesIndexedInts).

* Fix a mistake, use more singlethreadedness.

* WIP

* Tests, improvements.

* Style.

* See Spot bug.

* Remove unused method.

* Address review comments.

1) Read bitmaps even if we don't retain them.
2) Combine StringFrontCodedDictionaryEncodedColumn and ScalarStringDictionaryEncodedColumn.

* Add missing tests.

2023-06-28 10:30:27 -07:00

..

src

Properly read SQL-compatible segments in default-value mode. (#14142)

2023-06-28 10:30:27 -07:00

pom.xml

Added new SysMonitorOshi v0 using Oshi library (#14359)

2023-06-20 20:57:58 +05:30