PR #2065 fixed a bug with table btree seeks concerning boundaries
of leaf pages.
The issue was that if we were e.g. looking for the first key greater than
(GT) 100, we always assumed the key would either be found on the left child
page of a given divider (e.g. divider 102), which is incorrect. #2065 has more
discussion and documentation about this, so read that one for more context.
Anyway:
We already had similar handling for index btrees, but it was baked into
the `BTreeCursor` struct's seek handling itself, whereas #2065 handled this
on the VDBE side.
This PR unifies this handling for both table and index btrees by always doing
the additional cursor advancement in the VDBE.
Unfortunately, since indexes may also need to do an additional advance when they
are looking for an exact match, this resulted in a bigger refactor than anticipated,
since there are quite a few VDBE instructions that may perform a seek, e.g.:
`IdxInsert`, `IdxDelete`, `Found`, `NotFound`, `NoConflict`.
All of these can potentially end up in a similar situation where the cursor needs
one more advance after the initial seek.
For this reason, I have extracted a common VDBE helper `fn seek_internal()` which
all the interested VDBE instructions will call to delegate their seek logic.
- `OP_NewRowId` now generates new rowid semi randomly when the largest
rowid in the table is `i64::MAX`.
- Introduced new `LimboError` variant `DatabaseFull` to signify that
database might be full (SQLite behaves this way returning
`SQLITE_FULL`).
Now:
```SQL
turso> CREATE TABLE q(x INTEGER PRIMARY KEY, y);
turso> INSERT INTO q VALUES (9223372036854775807, 1);
turso> INSERT INTO q(y) VALUES (2);
turso> INSERT INTO q(y) VALUES (3);
turso> SELECT * FROM q;
┌─────────────────────┬───┐
│ x │ y │
├─────────────────────┼───┤
│ 1841427626667347484 │ 2 │
├─────────────────────┼───┤
│ 4000338366725695791 │ 3 │
├─────────────────────┼───┤
│ 9223372036854775807 │ 1 │
└─────────────────────┴───┘
```
Fixes: https://github.com/tursodatabase/turso/issues/1977
Reviewed-by: Jussi Saurio <jussi.saurio@gmail.com>
Closes#1985
`i64::MAX`. We do this by attempting to generate random values smaller
than `i64::MAX` for 100 times and returns `DatabaseFull` error on
failure
- Introduced `DatabaseFull` error variant
Fixes: https://github.com/tursodatabase/turso/issues/1977
This is done because the compiler is refusing to inline even after
adding inline hint.
- Get refvalues from directly from registers without using
`make_record`
when updating last_insert_rowid we call return_if_io!(cursor.rowid())
which yields IO on large records. this causes op_insert to insert and
overwrite the same row many times. we need a state machine to ensure
that the insertion only happens once and the reading of rowid can
independently yield IO without causing a re-insert.
Separates cursor.key_exists_in_index() into a state machine. The problem with
the main branch implementation is this:
`return_if_io!(seek)`
`return_if_io!(cursor.record())`
The latter may yield on IO and cause the seek to start over, causing an infinite
loop. With an explicit state machine we can control and prevent this.
Let's make sure we don't keep using a connection after it was dropped.
In case of executing a query that was closed we will try to rollback and
return early.
The `RowData` opcode is required to implement #1575.
I haven't found a ideal way to test this PR independently, but I
verified its functionality while working on #1575(to be committed soon),
and it performs effectively.
Reviewed-by: Jussi Saurio <jussi.saurio@gmail.com>
Closes#1756
This PR adds support for the instruction `IntegrityCk` which performs an
integrity check on the contents of a single table. Next PR I will try to
implement the rest of the integrity check where we would check indexes
containt correct amount of data and some more.
<img width="1151" alt="image" src="https://github.com/user-
attachments/assets/29d54148-55ba-480f-b972-e38587f0a483" />
Closes#1719
This PR adds support for table-valued functions for PRAGMAs (see the
[PRAGMA functions section](https://www.sqlite.org/pragma.html)).
Additionally, it introduces built-in table-valued functions. I
considered using extensions for this, but there are several reasons in
favor of a dedicated mechanism:
* It simplifies the use of internal functions, structs, etc. For
example, when implementing `json_each` and `json_tree`, direct access to
internals was necessary:
https://github.com/tursodatabase/limbo/pull/1088
* It avoids FFI overhead. [Benchmarks](https://github.com/piotrrzysko/li
mbo/blob/pragma_vtabs_bench/core/benches/pragma_benchmarks.rs) on my
hardware show that `pragma_table_info()` implemented as an extension is
2.5× slower than the built-in version.
Reviewed-by: Jussi Saurio <jussi.saurio@gmail.com>
Closes#1642
