Items from `index.tag` are stored as plain JS objects when no metatable
is defined. The `group by` clause wraps rows in `LuaTable` (`key`,
`group`) but leaves the individual `group` items as plain JS objects.
This causes `t.keys is not a function` errors when passing `row.group`
to APIs like `template.each` that expect `LuaTable` instances.
Signed-off-by: Matouš Jan Fialka <mjf@mjf.cz>
Evaluate all `order by` expressions once per item in a decorate pass,
then compare cached keys during sort. Reduces Lua eval calls from
*O(kn log n)* to *O(kn)* where *k* is the number of sort keys.
Signed-off-by: Matouš Jan Fialka <mjf@mjf.cz>
- Add iterative async stable merge sort (*O(n log n)*).
- Replace Quicksort with the new merge sort (kept Quicksort for tables).
- Update documentation (reorganize for logical flow, add SWO section
with invalid comparator example that really throws).
Signed-off-by: Matouš Jan Fialka <mjf@mjf.cz>
* support for custom comparators in LIQ `order by` clauses via the
`using` keyword.
* `using` is mutually exclusive with `asc`/`desc` and accepts either
a *named function* or an *inline anonymous function*. The comparator
receives two values and returns true if the first should come before the
second.
* `nulls first`/ `nulls last` works independently of `using`.
* `using` is now a reserved keyword (`kw`; this cannot be avoided but
the chance to collide with user scripts is negligable),
* documentation updated + polished a little
Signed-off-by: Matouš Jan Fialka <mjf@mjf.cz>
Implements `filter(where <cond>)` for aggregate functions in LIQ
queries which allows per-row conditional filtering within grouped
aggregates. Also extends test suite and documentation.
Signed-off-by: Matouš Jan Fialka <mjf@mjf.cz>
Extend the `order by` clause with optional `nulls first` and `nulls
last` modifiers following standard SQL semantics. Each sort key can
independently specify where `nil` values should appear in the result. By
default, ascending sorts place nulls last and descending sorts place
nulls first. An explicit nulls first or nulls last overrides this
default. The `asc` keyword is also now accepted as an explicit
alternative to the default ascending direction. Documentation and tests
were updated accordingly.
Signed-off-by: Matouš Jan Fialka <mjf@mjf.cz>
- Fix `group by` key building: populate array indices from
`keyParts` instead of only from `keyRecord`, which was empty for
some expressions (e.g. `tags[1]`).
- Fix collection handling: treat record-like `LuaTables` (no array part)
as items instead of extracting zero items.
- Update test suite.
Signed-off-by: Matouš Jan Fialka <mjf@mjf.cz>
* Fix `LUA_SQL_NULL` leaking into `order by` comparisons
Note: SQL `NULLS LAST` is now default behaviour!
* Fix `objectVariable` unset for empty groups
* Fix non-grouped `having` used wrong environment builder
Note: Queries similar to the following one now works correctly:
```sql
${query[[
from
tags.page
having
name == 'index'
]]}
```
* Fix `generateKey` did not handle `LUA_SQL_NULL`
* Refactor/deduplicate duplicated `order by` comparator
* Add `isSqlNull` helper
Signed-off-by: Matouš Jan Fialka <mjf@mjf.cz>
1. Fix `order by` inability to access `select` output aliases and
aggregate functions after `group by`.
2. Introduce `LUA_SQL_NULL` sentinel to preserve column ordering when
`select` expressions evaluate to `nil`.
Note: In Lua, setting a table key to `nil` deletes it so rows with
`nil` values lose those keys and produced inconsistent insertion
order across result tables.
Signed-off-by: Matouš Jan Fialka <mjf@mjf.cz>
* [LIQ] Extend with `group by` and `having` support
Also update documentation with extensive examples and add some parser
tests.
Note: `make generate` JS files included.
Signed-off-by: Matouš Jan Fialka <mjf@mjf.cz>
* Merge `liq-add-support-for-aggregators` branch
Signed-off-by: Matouš Jan Fialka <mjf@mjf.cz>
* Fix link, remove `_` example
Signed-off-by: Matouš Jan Fialka <mjf@mjf.cz>
* Wrap example LIQ queries inside `query [[ .. ]]` and replace `sql` code block type to `lua`
Signed-off-by: Matouš Jan Fialka <mjf@mjf.cz>
* Example self-consistency fix
Signed-off-by: Matouš Jan Fialka <mjf@mjf.cz>
* Fixed some queries
* Add experimental tags to LIQ aggregation/grouping
---------
Signed-off-by: Matouš Jan Fialka <mjf@mjf.cz>
Co-authored-by: Zef Hemel <zef@zef.me>
* Add result-or-promise (RP) exec model to interpreter (async-first).
* Add centralized table property access with fast misses.
* Update table string keys to be object map.
* Update error contexts to be more consistent and precise.
* Update evaluator to return either values or _Promises_.
* Update func calls, unary and bin operations, and expression lists.
* Update _stdlib_ to the changes and improve errors.
* Add tests to validate async control flow and error contexts.
* Add dedicated benches that isolate the _runtime_ from parsing.
Zef Hemel