Daniel Becker has uploaded a new patch set (#5). ( http://gerrit.cloudera.org:8080/19856 )
Change subject: IMPALA-12035: Impala accepts very big numbers but fails to store them correctly ...................................................................... IMPALA-12035: Impala accepts very big numbers but fails to store them correctly The statement select cast(9999999999999999999999 as BIGINT) correctly fails with the following message: ERROR: UDF ERROR: Decimal expression overflowed However, if the number is much bigger, no error is produced: select cast(999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999 as BIGINT) The root cause of the problem is this: - In the first case, the literal (9999999999999999999999) can fit into a DECIMAL and therefore is interpreted as such. This DECIMAL can't fit into a BIGINT, and this is checked, so the cast fails. - In the second case, the literal can't fit in a DECIMAL, so it is interpreted as a DOUBLE instead. This is not unreasonable as it fits in the range of DOUBLE, although of course there may be loss of precision. However, there is no check when casting from DOUBLE to BIGINT, and because the value is out of range for BIGINT this invokes undefined behaviour (probably leading to an incorrect value). This change adds checks to casts - from floating point types to integer types - from double to float These casts can invoke undefined behaviour in C++ and were not checked before this change. If the checks fail, an ERROR is raised. Testing: - Added unit tests in expr-tests.cc for the new checks Change-Id: Ibd97dee3c793a5caa95b1fe5d22b27b8c0f8275d --- M be/src/exprs/cast-functions-ir.cc M be/src/exprs/cast-functions.h M be/src/exprs/expr-test.cc M be/src/exprs/literal.cc M fe/src/main/java/org/apache/impala/analysis/CastExpr.java 5 files changed, 328 insertions(+), 40 deletions(-) git pull ssh://gerrit.cloudera.org:29418/Impala-ASF refs/changes/56/19856/5 -- To view, visit http://gerrit.cloudera.org:8080/19856 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-MessageType: newpatchset Gerrit-Change-Id: Ibd97dee3c793a5caa95b1fe5d22b27b8c0f8275d Gerrit-Change-Number: 19856 Gerrit-PatchSet: 5 Gerrit-Owner: Daniel Becker <daniel.bec...@cloudera.com> Gerrit-Reviewer: Csaba Ringhofer <csringho...@cloudera.com> Gerrit-Reviewer: Daniel Becker <daniel.bec...@cloudera.com> Gerrit-Reviewer: Impala Public Jenkins <impala-public-jenk...@cloudera.com> Gerrit-Reviewer: Kurt Deschler <kdesc...@cloudera.com> Gerrit-Reviewer: Michael Smith <michael.sm...@cloudera.com>
