Files
scylladb/test
Wojciech Mitros ae0d77257f mv: fix view_update_builder losing fragments across batch boundaries
When a mutation generates more view updates than max_rows_for_view_updates
(100), view_update_builder::build_some() splits the work into multiple
batches. There was a bug in how fragments were read between batches:

When should_stop_updates() returned true, the old code called stop()
which returned stop_iteration::yes without reading the next fragments.
On the next build_some() call, read_both_next_fragments() was called
at the start, which advanced BOTH readers - skipping any fragment that
was already read but not yet consumed. A row could be not consumed if
either:
- the 100th (last in the batch) update was a row insertion and we still
  had insertions/updates remaining
- the 100th (last in the batch) update was a row deletion and we still
  had deletions/updates remaining
For the most common case where work is split in batches, i.e. range
deletions, we couldn't hit this because range delete generates only
view row deletions.
On tables with a single materialized view, we also couldn't get this
for any batches with less than 50 statements (unless the batch also
contained range deletions), because one non-range-delete update can
generate up to 2 view updates.
Howeveer, for a range of scenarios outside these 2, we could lose
view updates, resulting in persistent inconsistencies.

The fix:
- read_*_next_fragment() now accept a stop_iteration parameter, so the
  next fragments are always read after consuming (even when stopping),
  but stop_iteration::yes is correctly propagated to break the loop.
- build_some() no longer re-reads fragments at the start. Instead, an
  initialize() method performs the initial read once at construction.
- because now we only advance readers after consuming, we won't advance
  readers after end_of_partition, so we extend the break condition to
  accept either readers evaluating to `false` or them being at the
  end_of_partition. We also handle the optimization with
  _skip_row_updates

Fixes: scylladb/scylladb#29155

Closes scylladb/scylladb#29498
2026-05-26 14:15:12 +02:00
..
2026-05-20 13:47:12 +03:00
2026-04-12 19:46:33 +03:00

Scylla in-source tests.

For details on how to run the tests, see docs/dev/testing.md

Shared C++ utils, libraries are in lib/, for Python - pylib/

alternator - Python tests which connect to a single server and use the DynamoDB API unit, boost, raft - unit tests in C++ cqlpy - Python tests which connect to a single server and use CQL topology* - tests that set up clusters and add/remove nodes cql - approval tests that use CQL and pre-recorded output rest_api - tests for Scylla REST API Port 9000 scylla-gdb - tests for scylla-gdb.py helper script nodetool - tests for C++ implementation of nodetool

If you can use an existing folder, consider adding your test to it. New folders should be used for new large categories/subsystems, or when the test environment is significantly different from some existing suite, e.g. you plan to start scylladb with different configuration, and you intend to add many tests and would like them to reuse an existing Scylla cluster (clusters can be reused for tests within the same folder).

To add a new folder, create a new directory, and then copy & edit its suite.ini.