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.
Fix codegen for binary functions and add fuzz test for math functions
(we need to compile `rusqlite` with `-DSQLITE_ENABLE_MATH_FUNCTIONS` in
order to bundle sqlite with math functions compiled)
Reviewed-by: Jussi Saurio (@jussisaurio)
Closes#1015
This is an attempt to move towards #881. I am not sure this is the
direction you want to take. In any case, I thought I would take a crack
at converting `values` from `Record` to private and see how bad it would
be.
In the end, as you can see, it is not so bad. I think performance-wise
it shouldn't be a bad hit with Rust's zero-cost abstraction. Also,
during the process I noticed a couple improvements that could be made
here and there but I honestly wanted to start with something small
enough that wouldn't be too hard to review.
Anyway, let me know if this is really how you would like to proceed.
Closes#962
Add fuzz test for string functions and fix 2 bugs in implementation of
`LTRIM/RTRIM/TRIM` and `QUOTE`:
- `QUOTE` needs to escape internal quote(`'`) symbols
- `LTRIM`/`RTRIM`/`TRIM` needs to check if they have additional argument
Closes#958
Tests for similar behavior already covered in TCL and Rust connection api tests. So flaky problem in these is not worth exploring. We just removed them.
Fix codegen for `CAST` expression and also adjust implementation of
`CAST: Real -> Int` because `SQLite` use "closest integer between the
REAL value and zero" as a CAST result.
Closes#956
Add `COALESCE` function in fuzz test and fix bug (found by fuzzer with
`COALESCE`) related to the resolution of labels which needs to be
resolved to next emitted instruction.
Before, code assumed that no two labels will need to be resolved to next
emitted instruction. But this assumption is wrong (at least in current
codegen logic) for example for following expression `COALESCE(0,
COALESCE(0, 0))`. Here, both `COALESCE` functions will create label and
resolve it to next emitted instruction in the end of generation. So, in
this case one of the labels will be actually "orphaned" and never be
assigned any position in the emitted code.
Closes#955
(after fixing complicated b-tree bugs - I want to end my day with the
joy of fixing simple bugs)
This PR fix bug in emit (which was introduced after switch from
`HashMap` to `Vec`) and also align `CASE` codegen in case of `NULL`
result from `WHEN` clause with SQLite behaviour.
Reviewed-by: Jussi Saurio <jussi.saurio@gmail.com>
Closes#953
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.
### What?
adding checkpoint result returning number of pages in wal and num pages
checkpointed.
Part of #696
### Context
SQLite returns in checkpoint result of calling `pragma wal_checkpoint;`
`0|3|3` while limbo returns `0|0|0`.
https://sqlite.org/pragma.html#pragma_wal_checkpoint
- 1st col: 1 (checkpoint SQLITE_BUSY) or 0 (not busy).
- 2nd col: # modified pages written to wal file
- 3rd col: # pages moved to db after checkpoint
This PR aims to add 2nd and 3rd column to the checkpoint result.
SQLite
```
sqlite3 test.db
sqlite> pragma journal_mode=wal;
wal
sqlite> pragma journal_mode;
wal
sqlite> create table t1 (id text);
sqlite> insert into t1(id) values (1),(2);
sqlite> select * from t1;
1
2
sqlite> pragma wal_checkpoint;
0|3|3
```
Limbo
```
./target/debug/limbo test.db
Limbo v0.0.13
Enter ".help" for usage hints.
limbo> pragma journal_mode;
wal
limbo> create table t1(id text);
limbo> insert into t1(id) values (1),(2);
limbo> select * from t1;
1
2
# current the 2nd and 3rd columns are hard coded in limbo to 0
limbo> pragma wal_checkpoint;
0|0|0
```
Closes#827
This PR fixes implementation of binary shift right/left instructions.
Before there were a minor incompatibility between limbo and sqlite
implementation in case when right shift second argument were more than
64 and first argument were negative. As sqlite implementation of right
binary shift is sign-extended - so `-1` should be returned in such case
when limbo returned zero.
This PR fixes this bug and also introduce a fuzz tests for arithemtic
expressions. This fuzz test were written with a help of
`GrammarGenerator` which allows to easily define probabilistic context-
free grammar and then later sample random strings from it.
Closes#867
