Adds initial support for window functions. For now, only existing
aggregate functions can be used as window functions—no specialized
window-specific functions are supported yet.
Currently, only the default frame definition is implemented:
RANGE BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW EXCLUDE NO OTHERS.
currently we always evaluate the binary expression, then coerce it
to zero/null with the `ZeroOrNull` instruction, and then emit a separate
jump.
this is fine for non-conditional expressions where we are using the value
itself (e.g. in a SELECT result column), but in conditionals we don't care
about that at all and just want to jump.
so: try to keep the spirit of code reuse, but still have distinct implementations
for conditionals and non-conditionals.
To be used in DBSP-based projections. This will compile an expression
to VDBE bytecode and execute it.
To do that we need to add a new type of Expression, which we call a
Register.
This is a way for us to pass parameters to a DBSP program which will be
not columns or literals, but inputs from the DBSP deltas.
SQLite does not store the rowid alias column in the record at all
when it is a rowid alias, because the rowid is always stored anyway
in the record header.
Different scan parameters are required for different table types.
Currently, index and iteration direction are only used by B-tree tables,
while the remaining table types don’t require any parameters. Planning
access to virtual tables, however, will require passing additional
information from the planner, such as the virtual table index (distinct
from a B-tree index) and the constraints that must be forwarded to the
`filter` method.
Extracts the core logic of IN from the conditional version, and uses the
conditional metadata to determine the jump. Then Uses the AddImm
operator we just added to force the integer conversion at the end (like
SQLite does).
Our compat matrix mentions a couple of opcodes: ToInt, ToBlob, etc.
Those opcodes do not exist.
Instead, there is a single Cast opcode, that takes the affinity as a
parameter.
Currently we just call a function when we need to cast. This PR fixes
the compat file, implements the cast opcode, and in at least one
instance, when explicitly using the CAST keyword, uses that opcode
instead of a function in the generated bytecode.
Closes: #1947
This PR replaces the `Name(pub String)` struct with a `Name` enum that
explicitly models how the name appeared in the source either as an
unquoted identifier (`Ident`) or a quoted string (`Quoted`).
In the process, the separate `Id` wrapper type has been coalesced into
the `Name` enum, simplifying the AST and reducing duplication in
identifier handling logic.
While this increases the size of some AST nodes (notably
`yyStackEntry`).
cc: @levydsa
Reviewed-by: Levy A. (@levydsa)
Reviewed-by: Preston Thorpe (@PThorpe92)
Closes#2251
Support for attaching databases. The main difference from SQLite is that
we support an arbitrary number of attached databases, and we are not
bound to just 100ish.
We for now only support read-only databases. We open them as read-only,
but also, to keep things simple, we don't patch any of the insert
machinery to resolve foreign tables. So if an insert is tried on an
attached database, it will just fail with a "no such table" error - this
is perfect for now.
The code in core/translate/attach.rs is written by Claude, who also
played a key part in the boilerplate for stuff like the .databases
command and extending the pragma database_list, and also aided me in
the test cases.
This commit replaces the `Name(pub String)` struct with a `Name` enum that
explicitly models how the name appeared in the source either as an
unquoted identifier (`Ident`) or a quoted string (`Quoted`).
In the process, the separate `Id` wrapper type has been coalesced into the
`Name` enum, simplifying the AST and reducing duplication in identifier
handling logic.
While this increases the size of some AST nodes (notably `yyStackEntry`),
it improves correctness and makes source structure more explicit for
later phases.
I ended up hitting #1974 today and wanted to fix it. I worked with
Claude to generate a more comprehensive set of queries that could fail
aside from just the insert query described in the issue. He got most of
them right - lots of cases were indeed failing. The ones that were
gibberish, he told me I was absolutely right for pointing out they were
bad.
But alas. With the test cases generated, we can work on fixing it. The
place where the assertion was hit, all we need to do there is return
true (but we assert that this is indeed a string literal, it shouldn't
be anything else at this point).
There are then just a couple of places where we need to make sure we
handle double quotes correctly. We already tested for single quotes in a
couple of places, but never for double quotes.
There is one funny corner case where you can just select "col" from tbl,
and if there is no column "col" on the table, that is treated as a
string literal. We handle that too.
Fixes#1974Closes#2152
I ended up hitting #1974 today and wanted to fix it. I worked with
Claude to generate a more comprehensive set of queries that could fail
aside from just the insert query described in the issue. He got most of
them right - lots of cases were indeed failing. The ones that were
gibberish, he told me I was absolutely right for pointing out they were
bad.
But alas. With the test cases generated, we can work on fixing it. The
place where the assertion was hit, all we need to do there is return
true (but we assert that this is indeed a string literal, it shouldn't
be anything else at this point).
There are then just a couple of places where we need to make sure we
handle double quotes correctly. We already tested for single quotes in a
couple of places, but never for double quotes.
There is one funny corner case where you can just select "col" from tbl,
and if there is no column "col" on the table, that is treated as a
string literal. We handle that too.
Fixes#1974
This PR provides Euclidean distance support for limbo's vector search.
At the same time, some type abstractions are introduced, such as
`DistanceCalculator`, etc. This is because I hope to unify the current
vector module in the future to make it more structured, clearer, and
more extensible.
While practicing Euclidean distance for Limbo, I discovered that many
checks could be done using the type system or in advance, rather than
waiting until the distance is calculated. By building these checks into
the type system or doing them ahead of time, this would allow us to
explore more efficient computations, such as automatic vectorization or
SIMD acceleration, which is future work.
Reviewed-by: Nikita Sivukhin (@sivukhin)
Closes#1986
Previously, the `jump_if_condition_is_true` flag was not respected. As a
result, for expressions like <`ISNULL`/`NOTNULL`> `OR` <rhs>, the <rhs>
expression was evaluated even when the left-hand side was true, and its
value was incorrectly used as the final result.
Previously, queries like:
```
SELECT
CASE WHEN c0 != 'x' THEN group_concat(c1, ',') ELSE 'x' END
FROM t0
GROUP BY c0;
```
would return incorrect results because c0 was not copied during the
aggregation loop into a register accessible to the logic processing the
grouped results (e.g., the CASE WHEN expression in this example).
The same issue applied to expressions in the HAVING and ORDER BY clauses.
