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
This PR aims to simplify text creation and to reduce allocation overhead
of creating a new OwnedValue::Text. Instead of creating Rc<String> every
time you need to create a text, you just pass the string slice and the
Rc<String> is created at the end. This change, at least on my machine,
has removed a lot of variability in the benchmarking performance, while
maintaining roughly the same performance.
Closes#961
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
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
Hi! This is my first PR on the project, so I apologize if I did not
follow a convention from the project.
#127
This PR implements json_quote as specified in their source:
https://www.sqlite.org/json1.html#jquote. It follows the internal doc
guidelines for implementing functions. Most tests were added from sqlite
test suite for json_quote, while some others were added by me. Sqlite
test suite for json_quote depends on json_valid to test for correct
escape control characters, so that specific test at the moment cannot be
done the same way.
Reviewed-by: Jussi Saurio <jussi.saurio@gmail.com>
Reviewed-by: Sonny (@sonhmai)
Closes#763
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.
- Remove eagerly allocated `name` from `ResultSetColumn`
- `ResultSetColumn` can calculate `name()` on demand:
- if it has an alias (`foo as bar`), use that
- if it is a column reference, use that
- otherwise return none, and callers can assign it a placeholder
name (like `column_1`)
- move the `plan.result_columns` and `plan.table_references` to
`Program` after preparing statement is done, so that column names can be
returned upon request
- make `name` in `Column` optional, not needed for pseudo tables and
sorters so avoids an extra string allocation
```sql
Prepare `SELECT 1`/Limbo/SELECT 1
time: [756.80 ns 758.27 ns 760.04 ns]
change: [-3.3257% -3.0252% -2.7035%] (p = 0.00 < 0.05)
Performance has improved.
Found 8 outliers among 100 measurements (8.00%)
2 (2.00%) low severe
3 (3.00%) low mild
1 (1.00%) high mild
2 (2.00%) high severe
Prepare `SELECT * FROM users LIMIT 1`/Limbo/SELECT * FROM users LIMIT 1
time: [1.4646 µs 1.4669 µs 1.4696 µs]
change: [-6.4769% -6.2021% -5.9137%] (p = 0.00 < 0.05)
Performance has improved.
Found 7 outliers among 100 measurements (7.00%)
1 (1.00%) low severe
3 (3.00%) low mild
3 (3.00%) high severe
Prepare `SELECT first_name, count(1) FROM users GROUP BY first_name HAVING count(1) > 1 ORDER BY cou...`
time: [3.7256 µs 3.7311 µs 3.7376 µs]
change: [-4.5195% -4.2192% -3.9309%] (p = 0.00 < 0.05)
Performance has improved.
Found 5 outliers among 100 measurements (5.00%)
1 (1.00%) low severe
2 (2.00%) low mild
2 (2.00%) high mild
```
Closes#898
This PR adds support for `json_set`.
There are three helper functions added:
1. `json_path_from_owned_value`, this function turns an `OwnedValue`
into a `JsonPath`.
2. `find_or_create_target`, this function is similar to `find_target`
with the added bonus of creating the target if it doesn't exist. There
is a caveat with this function and that is that it will create
objects/arrays as it goes, meaning if you send `{}` into it and try
getting the path `$.some.nested.array[123].field`, it will return
`{"some":{"nested":array:[]}}` since creation of `some`, `nested` and
`array` will succeed, but accessing element `123` will fail.
3. `create_and_mutate_json_by_path`, this function is very similar to
`mutate_json_by_path` but calls `find_or_create_target` instead of
`find_target`
Related to #127Closes#878
### 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
Add basic printf function support in limbo
Closes#886
This PR implements json_pretty. At the moment, support for jsonb is
being added, so this function suffers from the same limitations as in
json(x). Also, I have not found a way to implement the same conversion
of Blob -> String that SQLite does. From my own experimentation, I
believe SQLite converts blobs to a lossy ascii representation, but I
would appreciate some help on this.
Closes#860
We spend a lot of time especially in `GROUP BY` queries providing
helpful comments for `EXPLAIN`, even when the query is not an `EXPLAIN`.
So let's not do that
Closes#784
```sql
Prepare `SELECT first_name, count(1) FROM users GROUP BY first_name HAVING count(1) > 1 ORDER BY cou...
time: [4.2724 µs 4.2783 µs 4.2848 µs]
change: [-6.1063% -5.7376% -5.3626%] (p = 0.00 < 0.05)
Performance has improved.
```
doesn't affect the other trivial prepare benchmarks
Closes#875
The main difference between = and != is how null values are handled.
SQLite passes a flag "NULLEQ" to Eq and Ne to disambiguate that.
In the presence of that flag, NULL = NULL.
Some prep work is done to make sure we can pass a flag instead of a
boolean to Eq and Ne. I looked into the bitflags crate but got a bit
scared with the list of dependencies.
Warning:
The following query produces a different result for Limbo:
```
select * from demo where value is null or id == 2;
```
I strongly suspect the issue is with the OR implementation, though. The
bytecode generated is quite different.
Reviewed-by: Jussi Saurio <jussi.saurio@gmail.com>
Closes#847
The main difference between = and != is how null values are handled.
SQLite passes a flag "NULLEQ" to Eq and Ne to disambiguate that.
In the presence of that flag, NULL = NULL.
Some prep work is done to make sure we can pass a flag instead of a
boolean to Eq and Ne. I looked into the bitflags crate but got a bit
scared with the list of dependencies.
