* Website: Make manual build ref configurable
* [LIQ] Unify `from`, `select`, and `group by` clauses to use field lists
Query clauses `from`, `select`, and `group by` now accept the same field
syntax as Lua table constructors (`name = expr`, bare expr, or `[expr]
= expr`), giving them a consistent grammar and enabling named bindings
everywhere. #feature
What changed:
* New `FieldList` rule in `lua.grammar`. All three clauses now parse
their arguments through it instead of using expression lists or the
special `Name "=" exp` pattern.
* AST types `LuaFromClause`, `LuaSelectClause`, and `LuaGroupByClause`
now carry fields: `LuaTableField[]` instead of a single expression or
an expression array. The parser, static analysis helpers and the
evaluator are all updated to work with this new shape.
Named bindings in `select`
--------------------------
`select name, age` now derives column names from bare variable or
property access expressions so the result table has string keys (`name`,
`age`) rather than integer indices. Explicit naming still works.
Named bindings in `group by`
----------------------------
`group b`y fields can carry explicit aliases that propagate into the
post-grouping scope. For example:
```sql
group by
n = name
select {
label = n
}
```
The alias `n` is now visible in `select`, `having`, and `order by`.
Previously only the raw expression form (`name`) was bound and an
explicit alias was silently lost. #bugfix
A new `LuaGroupByEntry` type pairs each `group by` expression with its
optional alias. The environment builder binds every
declared alias to the corresponding key value, regardless of whether the
group key is a scalar or a multi-key table.
Named bindings in `from`
------------------------
`from p = page` continues to work as before. The clause now also accepts
the full field-list syntax which lays the groundwork for multi-source
from (cross join) in a future change. #todo #feature
Complete LIQ syntax now
-----------------------
Complete LIQ syntax (in Postgres documentation style) could be now
roughly expressed as follows: #todo #documentation
```text
query[[ clause [...] ]]
where clause is one of:
FROM field [, ...]
WHERE condition
GROUP BY field [, ...]
HAVING condition
SELECT field [, ...]
ORDER BY sort_key [, ...]
LIMIT count [, offset]
OFFSET start
where field is one of:
expression
name = expression
[expression] = expression
where sort_key is:
expression [ ASC | DESC ]
[ NULLS { FIRST | LAST } ]
[ USING name ]
[ USING FUNCTION function_body ]
where expression is any valid Lua expression, including:
aggregate_call
aggregate_call FILTER ( WHERE condition )
```
Signed-off-by: Matouš Jan Fialka <mjf@mjf.cz>
* Fix type error caused by earlier merge conflict resolution
Signed-off-by: Matouš Jan Fialka <mjf@mjf.cz>
* [LIQ] Cross-join support for multi-source `from`
Examples of what works now:
```
${query [[
from
x = { 1, 2 },
y = { 10, 20 },
z = { 100, 200 }
select {
sum = x + y + z
}
]]}
```
Or (more complicated three-way cross-join) to illustrate:
```
${query [[
from
s = {
{ id = 1, name = 'Eva', },
{ id = 2, name = 'Adam', },
{ id = 3, name = 'John', },
{ id = 4, name = 'Zef', },
},
c = {
{ id = 101, title = 'Mathematics', },
{ id = 102, title = 'Arts', },
{ id = 103, title = 'Physics', },
{ id = 104, title = 'Computer Science', },
{ id = 105, title = 'Literature', },
},
e = {
{ sid = 1, cid = 101, },
{ sid = 1, cid = 103, },
{ sid = 2, cid = 101, },
{ sid = 2, cid = 102, },
{ sid = 2, cid = 103, },
{ sid = 3, cid = 102, },
{ sid = 3, cid = 105, },
{ sid = 4, cid = 101, },
{ sid = 4, cid = 103, },
{ sid = 4, cid = 104, },
}
where
s.id == e.sid and
e.cid == c.id
order by
s.name
group by
s.name
having
s.name:match('^A') or
s.name:match('f$')
select
student = s.name:upper(),
courses = string_agg(c.title, ', '
order by c.title desc
)
]]}
```
Signed-off-by: Matouš Jan Fialka <mjf@mjf.cz>
---------
Signed-off-by: Matouš Jan Fialka <mjf@mjf.cz>
Co-authored-by: Zef Hemel <zef@zef.me>
* 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>
* [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>
* Improve documentation on string to number conversion (plus minor fixes of typos)
* Update Lua grammar to disallow unary plus
Signed-off-by: Matouš Jan Fialka <mjf@mjf.cz>
