OwnedValue has become a powerhouse of madness, mainly because I decided
to do it like that when I first introduced AggContext. I decided it was
enough and I introduced a `Register` struct that contains `OwnedValue`,
`Record` and `Aggregation`, this way we don't use `OwnedValue` for
everything make everyone's life harder.
This is the next step towards making ImmutableRecords the default
because I want to remove unnecessary allocations. Right now we clone
OwnedValues when we generate a record more than needed.
We currently have two value types, `Value` and `OwnedValue`. The
original thinking was that `Value` is external type and `OwnedValue` is
internal type. However, this just results in unnecessary transformation
between the types as data crosses the Limbo library boundary.
Let's just follow SQLite here and consolidate on a single value type
(where `sqlite3_value` is just an alias for the internal `Mem` type).
The way this will eventually work is that we can have bunch of
pre-allocated `OwnedValue` objects in `ProgramState` and basically
return a reference to them all the way to the application itself, which
extracts the actual value.
NoREC is a correctness property for testing optimizers, proposed by
Rigger and Su in [Detecting Optimization Bugs in Database Engines via
Non-Optimizing Reference Engine
Construction](https://www.manuelrigger.at/preprints/NoREC.pdf)
This PR adds a NoREC property to the tester.
Closes#973
I wanted to assist the current development in an up-to-date fashion,
this PR adds drop table(which is being implemented currently in
https://github.com/tursodatabase/limbo/pull/897) testing support to the
generator.
Unfortunately, we don't have feature flags in the simulator yet, so the
users should manually fix the generation probability in
`simulator/generation/plan.rs#L644` and
`simulator/generation/property.rs#L629`.
Closes#949
I am on a bit of a mission to revisit a lot of the ref counting, this
was an easy first win.
It seems to be a linear path of function calls or hashmaps which can own
the completions directly, no cloning needed.
Reviewed-by: Jussi Saurio <jussi.saurio@gmail.com>
Closes#912
We have been working with a very small subset of SQL so far. As a rather
lightweight next phase, I propose that we make the generated queries
more realistic, slowly converging into the type definitions in
`limbo/core`. This PR will gradually implement such advances, the first
commit demonstrates how `LIMIT` is added to `SELECT`.
Reviewed-by: Jussi Saurio <jussi.saurio@gmail.com>
Closes#793
Move result row to `ProgramState` to mimic what SQLite does where `Vdbe`
struct has a `pResultRow` member. This makes it easier to deal with result
lifetime, but more importantly, eventually lazily parse values at the edges of
the API.
The current status of the PR is halfway. The new framing of simulation
runner where `setup_simulation` is separated from `run_simulation`
allows for injecting custom plans easily. The PR is currently missing
the functionality to update the `SimulatorEnv` ad hoc from the plan, as
the environment tables were typically created during the planning phase.
The next steps will be to implement a function `fn
mk_env(InteractionPlan, SimulatorEnv) -> SimulatorEnv`, add `--load`
flag to the CLI for loading a serialized plan file, making a
corresponding environment and running the simulation.
We can optionally combine this with a `--save` option, in which we keep
a seed-vault as part of limbo simulator, corresponding each seed with
its generated plan and save the time to regenerate existing seeds by
just loading them into memory. I am curious to hear thoughts on this?
Would the maintainers be open to adding such a seed-vault? Do you think
the saved time would be worth the complexity of the approach?
Reviewed-by: Pere Diaz Bou <pere-altea@homail.com>
Closes#720
- add `--watch` flag
- start saving seeds in persistent storage
- make a separate version of execution functions that use `vector of interaction` instead of `InteractionPlan`
