Currently we have a Record, which is a dumb vector of cloned values.
This is incredibly bad for performance as we do not want to clone
objects unless needed. Therefore, let's start by introducing this type
so that any record that has already been serialized will be returned
from btree in the format of a simple payload with reference to payload.
Closes#1176
- Use `CheckpointResult::default()` instead of `CheckpointResult::new()`
- Correct WAL frame header salt and checksum handling
- Ensure frame ID is 1-based and adjust frame offset calculation
- Add `Default` implementation for `CheckpointResult`
- Use random values for WAL header salts
Currently we have a Record, which is a dumb vector of cloned values.
This is incredibly bad for performance as we do not want to clone
objects unless needed. Therefore, let's start by introducing this type
so that any record that has already been serialized will be returned
from btree in the format of a simple payload with reference to payload.
Fuzz testing is great for finding bugs, but until we fix the bugs,
failing CI runs out of the blue for unrelated PRs is not very
productive. Hopefully we can enable this soon again, but until then,
let's not fail the test suite all the time randomly.
There are two bugs in #1085.
1. `find_free_cell` accesses non-existent free blocks and returns their
size to `allocate_space`. This is out of range access error. The fix is
to add a loop termination condition that stops it when we hit the end of
the blocks
2. This bug is caused by `find_free_cell` some how swallowing the blocks
with size `4 bytes`. So `compute_free_space` consistently undercounts by
`4 bytes`. I've refactored that part of the code to make sure 4 sized
block are not deleted.
I've also added a unit test which proves these fixes work and also added
a function called `debug_print_freelist` which prints all free blocks of
a page.
For now I've silenced the `overflow_page` tests.
Fixes#1085Closes#1111
When I added frame reading support I thought, okay, who cares about the page id of this page it we read it from a frame because we don't need it to compute the offset to read from the file in this case. Fuck me, because it was needed in case we read `page 1` from WAL because it has a differnt `offset`.
Previously any block that has a size 4 is deleted resulting in the issue of computed free space
is less than 4 bytes when compared to expected free space.
This PR adds support for `DROP TABLE` and addresses issue
https://github.com/tursodatabase/limbo/issues/894
It depends on https://github.com/tursodatabase/limbo/pull/785 being
merged in because it requires the implementation of `free_page`.
EDIT: The PR above has been merged.
It adds the following:
* an implementation for the `DropTable` AST instruction via a method
called `translate_drop_table`
* a couple of new instructions - `Destroy` and `DropTable`. The former
is to modify physical b-tree pages and the latter is to modify in-memory
structures like the schema hash table.
* `btree_destroy` on `BTreeCursor` to walk the tree of pages for this
table and place it in free list.
* state machine traversal for both `btree_destroy` and
`clear_overflow_pages` to ensure performant, correct code.
* unit & tcl tests
* modifies the `Null` instruction to follow SQLite semantics and accept
a second register. It will set all registers in this range to null. This
is required for `DROP TABLE`.
The screenshots below have a comparison of the bytecodes generated via
SQLite & Limbo.
Limbo has the same instruction set except for the subroutines which
involve opening an ephemeral table, copying over the triggers from the
`sqlite_schema` table and then re-inserting them back into the
`sqlite_schema` table.
This is because `OpenEphemeral` is still a WIP and is being tracked at
https://github.com/tursodatabase/limbo/pull/768
Reviewed-by: Pere Diaz Bou <pere-altea@homail.com>
Closes#897
I don't know when and why we dropped log::* in favor of tracing but when it was done, it made relevant logs not appear any more while debugging so... I added test_log::test which helps by automatically adding info logs from trace package.
