If a regular row isn't present, no regular column restriction
(say, r=3) can pass since all regular columns are presented as NULL,
and we don't have an IS NULL predicate. Yet we just ignore it.
Handle the restriction on a missing column by return false, signifying
the row was filtered out.
We have to move the check after the conditional checking whether there's
any restriction at all, otherwise we exit early with a false failure.
Unit test marked xfail on this issue are now unmarked.
A subtest of test_tombstone_limit is adjusted since it depended on this
bug. It tested a regular column which wasn't there, and this bug caused
the filter to be ignored. Change to test a static column that is there.
A test for a bug found while developing the patch is also added. It is
also tested by test_tombstone_limit, but better to have a dedicated test.
Fixes#10357Closesscylladb/scylladb#20486
Issue #10357 is about a SELECT with a filter on a regular column which
incorrectly returns a static row without regular columns set (so the
filter would not have matched). We already have four tests reproducing
this issue, but each of them is a small part of a large tests translated
from Cassandra, making it hard to understand the scope of this bug.
So in this patch we add two new tests, one passing and one xfailing,
which clarify the scope of this bug. It turns out that the bug only
occurs when a partition has no clustering rows and only has a static
row. If the partition does have clustering rows - even if those don't
match the filter - the bug doesn't happen. The xfailing test is just
two statements long - a single INSERT and a single SELECT
Refs #10357.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closesscylladb/scylladb#15120
This patch adds two tests for two interesting edge cases in the behavior
of static columns in Scylla. We already have a lot of tests for static
columns in other frameworks (C++ unit tests, cql and dtest), but the two
cases here are issues where specifically we weren't sure how Cassandra
behaves in those cases - and this can most easily be checked in the
test/cql-pytest framework.
The first test, test_static_not_selected, is a reproducer for issue #10091.
This issue was reported by a user @aohotnik, who was surprised by the
fact that Scylla returns empty values, instead of nothing, when selecting
regular columns of a non-existent row if the partition has a static
column set. The test demonstrates a difference between Scylla and
Cassandra, so it is marked "xfail" - it passes on Cassandra and fails on
Scylla. If later we decide that both Scylla's and Cassandra's behaviours
are reasonable and both can be considered "correct", we can change this
test to except Scylla's result as well and it will beging to pass.
The second test, test_missing_row_with_static, shows that SELECT of a
non-existent row returns nothing - even if the partition has a static
column. The behavior in this case is identical in Scylla and Cassandra,
so this test passes. This contrasts with the analogous situation in LWT
UPDATE from issue #10081, where the IF condition is expected to see the
static column value.
Refs #10081
Refs #10091
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20220220120418.831540-1-nyh@scylladb.com>
