Adds initial limited support for CTEs.
- No MATERIALIZED
- No RECURSIVE
- No named CTE columns
- Only SELECT statements supported inside CTE
Basically this kind of WITH clause can just be rewritten as a subquery,
so this PR adds some plumbing to rewrite them using the existing
subquery machinery.
It also introduces the concept of a `Scope` where a child query can
refer to its parent, useful for CTEs like:
```
do_execsql_test nested-subquery-cte {
with nested_sub as (
select concat(name, '!!!') as loud_hat
from products where name = 'hat'
),
sub as (
select upper(nested_sub.loud_hat) as loudest_hat from nested_sub
)
select sub.loudest_hat from sub;
} {HAT!!!}
```
I think we need to expand the use of `Scope` to all of our identifier
resolutions (currently we don't explicitly have logic for determining
what a given query can see), but I didn't want to bloat the PR too much.
Hence, this implementation is probably full of all sorts of bugs, but
I've added equivalent tests for ALL the existing subquery tests,
rewritten in CTE form.
Closes#920
Add fuzz test for string functions and fix 2 bugs in implementation of
`LTRIM/RTRIM/TRIM` and `QUOTE`:
- `QUOTE` needs to escape internal quote(`'`) symbols
- `LTRIM`/`RTRIM`/`TRIM` needs to check if they have additional argument
Closes#958
Fix codegen for `CAST` expression and also adjust implementation of
`CAST: Real -> Int` because `SQLite` use "closest integer between the
REAL value and zero" as a CAST result.
Closes#956
Add `COALESCE` function in fuzz test and fix bug (found by fuzzer with
`COALESCE`) related to the resolution of labels which needs to be
resolved to next emitted instruction.
Before, code assumed that no two labels will need to be resolved to next
emitted instruction. But this assumption is wrong (at least in current
codegen logic) for example for following expression `COALESCE(0,
COALESCE(0, 0))`. Here, both `COALESCE` functions will create label and
resolve it to next emitted instruction in the end of generation. So, in
this case one of the labels will be actually "orphaned" and never be
assigned any position in the emitted code.
Closes#955
(after fixing complicated b-tree bugs - I want to end my day with the
joy of fixing simple bugs)
This PR fix bug in emit (which was introduced after switch from
`HashMap` to `Vec`) and also align `CASE` codegen in case of `NULL`
result from `WHEN` clause with SQLite behaviour.
Reviewed-by: Jussi Saurio <jussi.saurio@gmail.com>
Closes#953
Hi! This is my first PR on the project, so I apologize if I did not
follow a convention from the project.
#127
This PR implements json_quote as specified in their source:
https://www.sqlite.org/json1.html#jquote. It follows the internal doc
guidelines for implementing functions. Most tests were added from sqlite
test suite for json_quote, while some others were added by me. Sqlite
test suite for json_quote depends on json_valid to test for correct
escape control characters, so that specific test at the moment cannot be
done the same way.
Reviewed-by: Jussi Saurio <jussi.saurio@gmail.com>
Reviewed-by: Sonny (@sonhmai)
Closes#763
**Core delete tasks**:
- [x] Implement free page functionality
- [x] Clear overflow pages if any before deleting their cells using free
page.
- [x] Implement delete for leaf page
- [ ] Balance after delete properly
**Auxiliary tasks to make delete work properly**:
- [x] Implement block coalescing in `free_cell_range` to reduce
fragmentation.
- [x] Track page fragmentation in `free_cell_range`.
- [x] Update page offsets in `drop_cell` and update cell pointer array
after dropping a cell.
- [x] Add TCL tasks
Closes#455
--------
I will add support for balancing after delete once `balance_nonroot` is
extended. In the current state of `balance_nonroot` balancing won't work
after delete and corrupts page.
But delete itself is functional now.
Closes#785
Add basic printf function support in limbo
Closes#886
This PR implements json_pretty. At the moment, support for jsonb is
being added, so this function suffers from the same limitations as in
json(x). Also, I have not found a way to implement the same conversion
of Blob -> String that SQLite does. From my own experimentation, I
believe SQLite converts blobs to a lossy ascii representation, but I
would appreciate some help on this.
Closes#860
Closes#744
```sql
# Wanda = 9, Whitney = 11, William = 111
do_execsql_test column_alias_in_group_by_order_by_having {
select first_name as fn, count(1) as fn_count from users where fn in ('Wanda', 'Whitney', 'William') group by fn having fn_count > 10 order by fn_count;
} {Whitney|11
William|111}
```
Closes#864
This PR fixes a bug when index search used incorrect operator if index
column were the "rhs" in the expression (not "lhs" as usual, e.g.
`SELECT * FROM t WHERE 1 < rowid_alias`)
Reviewed-by: Jussi Saurio (@jussisaurio)
Closes#870
The main difference between = and != is how null values are handled.
SQLite passes a flag "NULLEQ" to Eq and Ne to disambiguate that.
In the presence of that flag, NULL = NULL.
Some prep work is done to make sure we can pass a flag instead of a
boolean to Eq and Ne. I looked into the bitflags crate but got a bit
scared with the list of dependencies.
Both () and = variants covered. It is important to make sure that
the transaction is a read transaction, so we cannot hide all that logic
inside update_pragma, and have to make our decision before that.
This PR closes#787. Chrono offers to format the string from an iterator
of Format Items. I created a custom iterator that only allows formatters
specified by sqlite. This approach however does not address the
inefficient way that julianday is calculated. Also, with this
implementation we avoid having to maintain a separate vendored package
for strftime that may become incompatible with Chrono in the future.
Closes#792
#739
Started adding support for `LIMIT...OFFSET...`
- New `OffsetLimit` opcode
- `OFFSET` is now supported for:
- `SELECT...LIMIT...OFFSET`
- `SELECT...GROUP BY...LIMIT...OFFSET`
- `SELECT...ORDER BY...LIMIT...OFFSET`
- Subqueries for `SELECT` statements
**In progress/todo**
- [x] Testing
- [x] Handle negative offset value
- **(will make in separate PR)** Add support for
`DELETE...LIMIT...OFFSET`
- **(will make in separate PR)** Use `limit + offset` sum register from
`OffsetLimit` to constrain number of records inserted into sorter
Closes#779
Allow us to write queries like:
SELECT name, type, sql FROM sqlite_schema where sql isnull
and
SELECT name, type, sql FROM sqlite_schema where sql not null
Reviewed-by: Jussi Saurio <jussi.saurio@gmail.com>
Closes#829
