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.
Matouš Jan Fialka