Currently, we have a borrow problem because parse_schema_rows() already
borrows `schema`, but then `apply_view_deltas` does the same:
```
thread 'main' panicked at core/vdbe/mod.rs:450:49:
already mutably borrowed: BorrowError
stack backtrace:
0: __rustc::rust_begin_unwind
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/panicking.rs:697:5
1: core::panicking::panic_fmt
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/core/src/panicking.rs:75:14
2: core::cell::panic_already_mutably_borrowed
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/core/src/cell.rs:799:5
3: core::cell::RefCell<T>::borrow
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/core/src/cell.rs:987:25
4: turso_core::vdbe::Program::apply_view_deltas
at ./core/vdbe/mod.rs:450:26
5: turso_core::vdbe::Program::commit_txn
at ./core/vdbe/mod.rs:468:9
6: turso_core::vdbe::execute::op_halt
at ./core/vdbe/execute.rs:1954:15
7: turso_core::vdbe::Program::step
at ./core/vdbe/mod.rs:430:19
8: turso_core::Statement::step
at ./core/lib.rs:1914:23
9: turso_core::util::parse_schema_rows
at ./core/util.rs:91:15
10: turso_core::Connection::parse_schema_rows::{{closure}}
at ./core/lib.rs:1518:17
11: turso_core::Connection::with_schema_mut
at ./core/lib.rs:1625:9
12: turso_core::Connection::parse_schema_rows
at ./core/lib.rs:1515:9
```
However, this is a read transaction and views are not even enabled,
let's just make `apply_view_deltas()` return early if there's no
processing needed, to skip the schema borrow altogether.
Currently, the simulator complains of the following error:
```
Error: failed with error: 'attempt to multiply with overflow'
```
However, we don't enable views in the simulator so -- despite being an
issue -- we should never see this. Let's fix `op_delete()` some more not
to not even call rowid() unless view processing is enabled.
Implement very basic views using DBSP
This is just the bare minimum that I needed to convince myself that this
approach will work. The only views that we support are slices of the
main table: no aggregations, no joins, no projections.
* drop view is implemented.
* view population is implemented.
* deletes, inserts and updates are implemented.
much like indexes before, a flag must be passed to enable views.
Closes#2530
This is just the bare minimum that I needed to convince myself that this
approach will work. The only views that we support are slices of the
main table: no aggregations, no joins, no projections.
drop view is implemented.
view population is implemented.
deletes, inserts and updates are implemented.
much like indexes before, a flag must be passed to enable views.
When building views (soon), it will be important to know which table
is being deleted. Getting from the cursor id is very cumbersome.
What we are doing here is symmetrical to op_insert, and sqlite also
passes table information in one of the registers (p4)
We should be allocator-agnostic. It is pretty limiting for us to force a
user to use a particular allocator. This is specially restricting for
`no_std` in the future.
Reviewed-by: bit-aloo (@Shourya742)
Reviewed-by: Preston Thorpe <preston@turso.tech>
Closes#2481
This fix ensures that `WHERE` conditions are emitted after the `LEFT
JOIN` match flag is set, so rows from the right table are properly
filtered, even when they are `NULL` due to the outer join.
Previously, the query below would return rows where `products.price` was
`NULL`:
```sql
SELECT users.id, price
FROM users
LEFT JOIN products ON users.id = products.id
WHERE products.price IS NOT NULL;
```
Reviewed-by: Jussi Saurio <jussi.saurio@gmail.com>
Closes#2501
