Since page cache is now shared by default, we need to cache pages by
page number and something else. I chose to go with max_frame of
connection, because this connection will have a max_frame set until from
the start of a transaction until the end of it.
With key pairs of (pgno, max_frame) we make sure each connection is
caching based on the snapshot it is at as two different connections
might have the same pageno being using but a different frame. If both
have same max_frame then they will share same page.
Since we expect to ensure thread safety between multiple threads in the
future, we extract what is important to be shared between multiple
connections with regards to WAL/Pager.
This is WIP so I just put whatever feels like important behind a RwLock
but expect this to change to Atomics in the future as needed. Maybe even
these locks might disappear because they will be better served with
transaction locks.
This also includes addition of unsafe Sync/Send + UnsafeCell in Pages.
Closes#415
This includes an inner struct in Page wrapped with Unsafe cell to access
it. This is done intentionally because concurrency control of pages is
handled by pages and not by the page itself.
Since we expect to ensure thread safety between multiple threads in the
future, we extract what is important to be shared between multiple
connections with regards to WAL.
This is WIP so I just put whatever feels like important behind a RwLock
but expect this to change to Atomics in the future as needed. Maybe even
these locks might disappear because they will be better served with
transaction locks.
I'd love to contribute to Limbo, but wrapping my head around the whole
project is hard.
I decided to start by creating a diagram of a typical flow so that other
potential contributors might have an easier time :)
LMK if this is useful, I can create more of those when I dig deeper.
Closes#456
This PR prevents input from being evaluated in the case of an incomplete
statement entered, allowing the user to continue the query on following
lines.
This matches the behavior of the sqlite CLI by alerting the user how
many parenthesis are currently open (up to 9) `(x1...`, or too many
closed `(!...` and only processes `.`commands when they are the only
input.
>sqlite
fixes#450Closes#457
add [soundex](https://www.sqlite.org/lang_corefunc.html#soundex) scalar
function.
it seems that sqlite did not enable `soundex()` function by default
unless build it with `SQLITE_SOUNDEX`, while the sqlite in the ci
workflow did not enable it. this pr skipped the test over `soundex()`
temporarily in the `scalar-function.test` file.
Closes#453
Love the project, been following your blog posts for quite a while now.
I asked on Discord prior to submitting this, just because I didn't see a
specific issue for this feature... but if this PR is out of scope for
contributors, feel free to close it as I just had a good time hacking on
it.
This PR adds support for `BitAnd`, `BitOr`, and `BitNot` operators in
the vdbe, as well as unary expressions applied to aggregate functions;
which was needed in order to have `BitNot` support the same tests that
the other operators had.
*Also added unary negation of function calls, because since unary ops
were added, I figured adding support for the other existing unary
operator might be in scope, but lmk if not.
Let me know if there is any more tests or documentation to add/improve.
Closes#445
