panic: index out of bounds with DISTINCT and ORDER BY over expr

[philip-stoev]

What version of Materialize are you using?

materialized v0.7.2-dev (148440965)

What was the issue?

DISTINCT does not play well with ORDER BY with an expression:

2021-03-08T09:09:18.216747Z ERROR panic: index out of bounds: the len is 1 but the index is 1
thread: <unnamed>
location: src/sql/src/plan/query.rs:346:33
version: 0.7.2-dev (14844096530f6dc83e56b0f97417861a50c53ad9)
backtrace:
   0: materialized::handle_panic
             at src/materialized/src/bin/materialized/main.rs:618:21
   1: core::ops::function::Fn::call
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/core/src/ops/function.rs:70:5
   2: std::panicking::rust_panic_with_hook
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/std/src/panicking.rs:597:17
   3: std::panicking::begin_panic_handler::{{closure}}
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/std/src/panicking.rs:499:13
   4: std::sys_common::backtrace::__rust_end_short_backtrace
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/std/src/sys_common/backtrace.rs:141:18
   5: rust_begin_unwind
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/std/src/panicking.rs:495:5
   6: core::panicking::panic_fmt
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/core/src/panicking.rs:92:14
   7: core::panicking::panic_bounds_check
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/core/src/panicking.rs:69:5
   8: <usize as core::slice::index::SliceIndex<[T]>>::index
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/core/src/slice/index.rs:182:10
      core::slice::index::<impl core::ops::index::Index<I> for [T]>::index
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/core/src/slice/index.rs:15:9
      <alloc::vec::Vec<T> as core::ops::index::Index<I>>::index
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/alloc/src/vec.rs:1939:9
      sql::plan::query::try_push_projection_order_by::{{closure}}
             at src/sql/src/plan/query.rs:346:33
      <core::slice::iter::Iter<T> as core::iter::traits::iterator::Iterator>::all
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/core/src/slice/iter/macros.rs:217:25
      sql::plan::query::try_push_projection_order_by
             at src/sql/src/plan/query.rs:346:8
   9: sql::plan::query::plan_view_select
             at src/sql/src/plan/query.rs:1281:21
  10: sql::plan::query::plan_query
             at src/sql/src/plan/query.rs:763:24
  11: sql::plan::query::plan_root_query
             at src/sql/src/plan/query.rs:299:44
  12: sql::plan::statement::dml::describe_select
             at src/sql/src/plan/statement/dml.rs:105:9
  13: sql::plan::statement::describe
             at src/sql/src/plan/statement.rs:145:36
  14: coord::coord::describe
             at src/coord/src/coord.rs:3603:17
  15: coord::coord::Coordinator::handle_declare
             at src/coord/src/coord.rs:922:20
  16: coord::coord::Coordinator::message_command::{{closure}}
             at src/coord/src/coord.rs:762:30
      <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/core/src/future/mod.rs:80:19
      coord::coord::Coordinator::serve::{{closure}}
             at src/coord/src/coord.rs:412:42
  17: <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/core/src/future/mod.rs:80:19
      tokio::park::thread::CachedParkThread::block_on::{{closure}}
             at /home/pstoev/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-1.2.0/src/park/thread.rs:263:54
      tokio::coop::with_budget::{{closure}}
             at /home/pstoev/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-1.2.0/src/coop.rs:121:9
      std::thread::local::LocalKey<T>::try_with
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/std/src/thread/local.rs:272:16
      std::thread::local::LocalKey<T>::with
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/std/src/thread/local.rs:248:9
      tokio::coop::with_budget
             at /home/pstoev/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-1.2.0/src/coop.rs:114:5
      tokio::coop::budget
             at /home/pstoev/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-1.2.0/src/coop.rs:98:5
      tokio::park::thread::CachedParkThread::block_on
             at /home/pstoev/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-1.2.0/src/park/thread.rs:263:31
  18: tokio::runtime::enter::Enter::block_on
             at /home/pstoev/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-1.2.0/src/runtime/enter.rs:151:13
      tokio::runtime::thread_pool::ThreadPool::block_on
             at /home/pstoev/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-1.2.0/src/runtime/thread_pool/mod.rs:71:9
  19: tokio::runtime::Runtime::block_on
             at /home/pstoev/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-1.2.0/src/runtime/mod.rs:452:43
  20: coord::coord::serve::{{closure}}::{{closure}}
             at src/coord/src/coord.rs:3470:17
      std::sys_common::backtrace::__rust_begin_short_backtrace
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/std/src/sys_common/backtrace.rs:125:18
  21: std::thread::Builder::spawn_unchecked::{{closure}}::{{closure}}
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/std/src/thread/mod.rs:474:17
      <std::panic::AssertUnwindSafe<F> as core::ops::function::FnOnce<()>>::call_once
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/std/src/panic.rs:322:9
      std::panicking::try::do_call
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/std/src/panicking.rs:381:40
      std::panicking::try
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/std/src/panicking.rs:345:19
      std::panic::catch_unwind
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/std/src/panic.rs:396:14
      std::thread::Builder::spawn_unchecked::{{closure}}
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/std/src/thread/mod.rs:473:30
      core::ops::function::FnOnce::call_once{{vtable.shim}}
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/core/src/ops/function.rs:227:5
  22: <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/alloc/src/boxed.rs:1307:9
      <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/alloc/src/boxed.rs:1307:9
      std::sys::unix::thread::Thread::new::thread_start
             at /rustc/e1884a8e3c3e813aada8254edfa120e85bf5ffca/library/std/src/sys/unix/thread.rs:71:17
  23: start_thread
  24: clone

Is the issue reproducible? If so, please provide reproduction instructions.

DROP TABLE IF EXISTS t1;
CREATE TABLE t1 (f1 INTEGER);
SELECT DISTINCT f1 FROM t1 ORDER BY f1 + 1;