Null filtering problems when zonemaps enabled and data cotain NULLs
Details
| Detail name | Value |
|---|---|
| Changelog Number | 19613 |
| Type | Bug |
| Status | Resolved |
| Affected Versions | Exasol 8.24.0 |
| Fix Versions | Exasol 8.26.0 |
| Resolution Date | 2024-03-22 |
Description
In some cases, queries containing columns that use the Zonemaps feature may give false results in queries involving complex filtering and the NULL values being present in the data.
You can verify if a column is using Zonemaps with the following queries:
SELECT COLUMN_NAME, COLUMN_IS_ZONEMAPPED FROM EXA_ALL_COLUMNS WHERE COLUMN_TABLE = 'my_table';
or
DESCRIBE my_table;
Workaround
Set the database parameter -zonemapUseForFilterRaw=0.
Fix
In these instances, the query runs as expected.
