3. A Difficult Case "TPC-H Q8" is a test query from the Transaction Processing Performance Council. The query planners in SQLite versions 3.7.17 and earlier do not choose good plans for TPC-H Q8. And it has been determined that no ... 

 ... If temporary files are store in memory (which is not the default behavior, but is sometimes selected by applications using either -DSQLITE_TEMP_STORE or PRAGMA temp_store) and if a SAVEPOINT is rolled back and then subsequent changes within the same transaction ...