--- doc: title: 'Querying: the filter line' guide: slug: querying brief: the filter line, with examples description: >- The filter grammar every door here speaks, with worked examples: presence and absence, contains, comparisons, ranges, time phrases, walking a reference, counting, paging, full text — and why a row carries only the components its filter named. --- # Querying: the filter line One grammar reads an app's store, and every door speaks it: `query()` and `subscribe()` on the page, `GET ./api/query` underneath them, `graph_query` at the connector, a `query` in the app's own `tools.json`, and `env.STORE.fetch` from a worker. This page is that grammar with its examples — what selects rows, what a row comes back carrying, and the handful of things this store will not do. The examples are a kitchen app: a `vocab.json` declaring { "recipe": { "serves": "number", "minutes": "number", "cuisine": "text" }, "chore": { "every": "number" }, "reading": { "pages": "number", "started": "time", "done": "bool" } } beside the platform's own words — `doc`, `task`, `comment`, `archived`, `created` and the rest. ## The shape of a line A filter line is predicates joined by `&`. Each one is a dot, a component, a column, an operator, a value: .recipe.minutes<=30 ^ ^ ^ ^ | | | value | | operator | column of that component component await query('.recipe.minutes<=30&.doc?') GET ./api/query?.recipe.minutes<=30&.doc? Every predicate must hold — `&` is an intersection, never an "or". (Any-of lives inside one predicate, below.) A predicate ends where the next `&` begins, so two of them run together is not a longer filter, it is a mistake the store names: .recipe!.doc! → presence filters end at !: .recipe! — join filters with &: .recipe!&.doc! Your own words route QUALIFIED only — `.recipe.serves`, never `.serves` — so a word you invent can never change what `.title` means in somebody else's store. The platform's columns do route bare (`.title~=lemon` is `.doc.title~=lemon`), but write the component anyway: it reads better, and it never becomes ambiguous. An EMPTY line selects nothing. There is no "everything" — `query('')` and a bare `query('limit=50')` both answer `[]`. To list what you saved, name the component it wears: `.doc!`, `.recipe!`. ## Asking for a component Four ways to name a component rather than one of its columns: .recipe! has a recipe .recipe= has no recipe .recipe? asks for the recipe without filtering on it * every component this store holds (the debugging form) `!` and `=` SELECT. `?` selects nothing and screens nothing — it only asks for the component to ride along on whatever the rest of the line selected: await query('.chore!&.completed=&.doc?') // chores not yet done await query('.recipe!&.doc?') // recipes, with their titles `?` is safe over a word this store never planted: a request is not an assertion, so `.recipe!&.loan?` answers the recipes and simply leaves the loan off. `.loan!` over an unplanted word is refused instead, because an empty answer would lie about what is there. `*` answers every component of every row it selected. Use it when you are looking rather than drawing: await query('.doc.title~=drizzle&*') It is part of the line, so it rides wherever a line goes: `subscribe()` keeps answering the same query, and its frames carry the same whole rows. ## What an answer carries **A row carries only the components its filter NAMED.** This is the one rule to hold on to, because the mistake it prevents is a page that draws `undefined`. A row is `{kind, entity: {eid, num}, ...those components}`. So this is the wrong page: for (let r of await query('.recipe!')) { draw(r.doc.title) // TypeError: no doc on the row } → [{ kind: 'recipe', entity: {eid: '940d…', num: 1}, recipe: {serves: 4, minutes: 20, cuisine: 'american'} }] and this is the right one: for (let r of await query('.recipe!&.doc?')) { draw(r.doc.title, r.recipe.minutes) } → [{ kind: 'recipe', entity: {eid: '940d…', num: 1}, doc: {title: 'Pancakes', body: 'flour, milk, eggs'}, recipe: {serves: 4, minutes: 20, cuisine: 'american'} }] Anything a predicate mentions counts as naming it, whichever operator it wears: `.doc.title~=cake` carries the doc, `.task.status=open` carries the task, `.created.at=today` carries the stamp. Three things do NOT name one: an absence (`.archived=` asks for rows without one — there is nothing to carry), the `*` form, which asks for all of them, and a bare WORD, which searches the docs without naming anything to leave out — so a line that is only words answers whole entities, like `id=`. A column of yours that nothing has written is on the row with the value `null`, not missing from it, so test the value and not `in`. The platform's `doc.title` has a default and answers `''` instead. `entity` and `kind` ride every row: `entity.eid` is the address to write back to, `entity.num` is the number the store minted in order, and `kind` is what the entity is — the first component it wears, your own word included. Three kinds of row are left out of a listing unless the filter names them: the platform's stamps (`.created!`, `.updated!`), the platform's own error rows (`.exception!`, `.error!`), and the `person` rows the store keeps so a byline has a name (`.person!`). What comes back is what your app saved. `subscribe(filter, cb)` answers the same rows through the same rule, so a page swaps one for the other and nothing else changes. ## The operators .recipe.cuisine=thai equals .recipe.cuisine!=thai not .doc.title~=drizzle contains, case-insensitive, literal .recipe.minutes<30 less than .recipe.minutes<=30 at most .recipe.serves>4 more than .recipe.serves>=4 at least .recipe.cuisine=thai,british any of .recipe.minutes=20..35 a range, both ends included .recipe.minutes=20...35 a range, the end excluded .recipe.cuisine= the column is empty or absent .recipe.cuisine~= the column is there at all A number column compares numerically and every other column as text, which is why an ISO stamp compares correctly as text. A comparison a column's type cannot answer — `.recipe.serves>many` — is refused rather than guessed at. A list and a range are values, not extra syntax: `.recipe.cuisine!=thai,indian` is "neither", and `.recipe.minutes!=20..35` is "outside that band". **`!=` also matches a row that lacks the column entirely** — nothing there is not `thai`. When you mean "has a cuisine, and it is not thai", say both: await query('.recipe!&.recipe.cuisine!=thai&.doc?') `~=` is a plain substring test on the stored text, not full-text search: it finds `drizzle` inside `Lemon drizzle`, and it will not stem, rank, or match across a word boundary. Bare words do that (below). ## Values, by type The platform's own columns are TYPED, and a value that cannot be one is refused loudly rather than quietly matching nothing: .task.status=finished → task.status is one of open, wip, done, cancelled — got 'finished' .filed.priority=high → priority is a finite number, optionally P-prefixed (P2, p02, 1.5) — got 'high' - **text** — as typed. `.doc.title~=cake` - **number** — `.recipe.serves>=4`, decimals fine. - **enum** — `task.status` is `open`, `wip`, `done` or `cancelled`. It is read, never written: `.task.status=done` is the entity wearing a `completed`. - **priority** — a number, and `P` is optional: `.filed.priority<=2` and `.filed.priority<=P2` ask the same thing. - **time** — a stamp or a phrase; the next section is only about those. - **url** — text with a shape. Quote it (below), or the `&` in its query string starts a second predicate. - **eid** — a reference to another entity, by its eid: `.comment.target=940d…`, `.filed.assignee=dc5e…`, `.created.by=`. Your OWN columns are a different bargain: they are stored as given and compared as text, with no parsing on either side. Two consequences worth knowing before you design a component: - A `bool` of yours lands in the store as `1` or `0`, so filter it that way — `.reading.done=1` finds the finished ones, `.reading.done=true` finds nothing. - A `time` of yours is kept verbatim and compared as text, so write ISO stamps (`new Date().toISOString()`) and compare with ISO: `.reading.started>=2026-01-01` works, while `.reading.started=today` matches only a row that literally says "today". Time PHRASES are for the platform's stamps. Numbers of yours still compare as numbers — `.recipe.serves>=4` — because both sides read as numbers. ## Time phrases A time phrase is a RANGE, and the operator picks which edge of it you mean: = within it .created.at=today >= from its start .created.at>=2026-01-01 <= until its end .created.at<=yesterday > after it ends .created.at>last-week < before it starts .created.at=1-hour-ago') await query('.doc!&.created.at>="1 hour ago"') A phrase is read fresh every time the query runs, so a saved `today` still means today tomorrow. Weeks start Monday. Day boundaries are local time. ## The platform's stamps Every row the store keeps is stamped with who saved it and when. The stamps sit in components of their own, so they are asked for by name and left out of a listing that does not name them: .created! who saved it and when .created.at when (time) .created.by who (a reference) .updated.at when it last changed .updated.by who changed it await query('.recipe!&.created!&.doc?') → [{ kind: 'recipe', entity: {…}, doc: {title: 'Lemon drizzle', body: '…'}, created: {by: {eid: 'dc5e…', name: 'Maya'}, at: '2026-09-03T12:59:27.876Z', via: null}, recipe: {serves: 8} }] A reference to somebody this store has met answers `{eid, name}`, so one query draws a list with its bylines. Anything else stays the bare eid. `at` and `by` are shared by several components, so spell out which one you mean: `.created.at`, `.updated.by`, `.completed.at`, `.archived.at`. Some lines that come up: .doc!&.created.by=&.doc? what this person saved .doc!&.updated.at>=today&.doc? what changed today .doc!&.created.by!&.doc? the rows that have a byline .doc!&.created.at=last-week&.created! last week's, with the stamp ## Quoting Quotes hold a value together against both separators — whitespace and `&`: await query('.doc.title~="Lemon drizzle"') await query('.web.url="https://x.test/p?a=1&b=2"&.web?') Unquoted, the `&` in that URL would end the predicate and start a second one. Quoting is the mechanism here; percent-encoding a value with an `&` in it does not survive the trip, because the door decodes each segment before the grammar reads the line. Quote it. A value with a space but no `&` survives on its own (`.doc.title~=Lemon drizzle` is one predicate), but only until something else joins the line. Quoting always works, so quote. ## Walking a reference A dotted path walks a reference column and tests a column on the far side. Every hop but the last must be a reference: .comment.target.doc.title~=Pancakes comments on the pancake recipe .filed.project.doc.title~=Kitchen tasks in the project called Kitchen .assignee.title~=maya bare: filed.assignee → doc.title Only the platform's columns can be references — a `vocab.json` column is `text`, `number`, `bool`, `time` or `url` — so paths walk `comment.target`, `filed.project`, `filed.assignee`, `attachment.blob`, and the `by` of each stamp. Point at another entity from your own component by keeping its eid in a `text` column; it holds the address, but a path will not walk it. The PLURAL form walks the other way — the entities pointing back at this one: .comments! has at least one comment .comments= has none .comments>=2 has two or more (any comparison works) .comments.doc.body~=butter has SOME comment mentioning butter .comments!.doc.body~=butter has NONE mentioning butter .comments!.doc.body!=butter every comment mentions it (De Morgan) The name is the component's plural — `.comments` are the entities whose `comment.target` names this row. When a component has two reference columns the name says which one: `.tasks_project` are the projects that have tasks, `.tasks_assignee` the people who do; `.attachments` are the blobs a file row points at. // the recipes nobody has said anything about await query('.recipe!&.comments=&.doc?') // whoever has been given something to do await query('.tasks_assignee!&.doc?') And `.refs` is the union of all of them — everything pointing at one entity, by whichever column: await query(`.refs=${eid}&.doc?`) // what mentions this await query('.refs=&.doc?') // what mentions nothing ## Counting and tallying Three directives answer a VALUE instead of rows. They ride beside the filters that select what they reduce, and they read from the index — a page that wants a number asks for the number, never for the rows to count. await query('.recipe!&.count!') → {count: 3} await query('.recipe!&.tally=recipe.cuisine') → {tally: {american: 1, british: 1, thai: 1}} await query('.recipe!&.distinct=recipe.cuisine') → {distinct: ['american', 'british', 'thai']} `.count!` counts what the rest of the line selects. `.tally=` counts each value of one column; `.distinct=` answers those values themselves, sorted. Both name one column, never a path, and your own columns must be spelled with their component — `.tally=recipe.cuisine`, not `.tally=cuisine`. The answer is an object, not an array, so a page has to branch on which it asked for. Ask one aggregate per line: two in one line and only the first answers. let { count } = await query('.chore!&.completed=&.count!') badge.textContent = `${count} to do` ## Windows and paging A window bounds the ANSWER without changing what matches. limit=20 the newest 20 matches after= continue below a spine num you already have A plain listing is oldest first, by the number the store minted. A WINDOWED listing is the newest that many — still in that same oldest-first order among themselves. So `limit` is the front page of a feed, and paging walks backwards: let page = await query('.doc!&limit=20') let oldest = page[0].entity.num let older = await query(`.doc!&limit=20&after=${oldest}`) `after` means "older than this num", so the cursor is the SMALLEST num you hold, not the largest. Both spellings work — `limit=20` and `.limit=20` are the same window — and a bad bound is refused rather than dropped: .limit=abc → .limit takes a whole number: .limit=200 Remember that a window without a filter is nothing: `limit=50` alone answers `[]`, because an empty line selects nothing. ## One entity, whole await query(`id=${eid}`) `id=` addresses instead of selecting, and an address names no component to leave out — so it answers the whole bundle, stamps and all. Several at once is a comma list, or a repeat: await query(`id=${a},${b}`) Name a component beside it and you are back to the ordinary rule: `id=&.doc?` answers that entity's doc alone. Anything the store minted an eid for is addressable this way, including a blob you uploaded. ## Words A bare word is a full-text term over every doc — title and body — and the answer comes back ranked, best first: await query('lemon') await search('lemon') // the same door await query('lemon&.recipe!&.doc?') // ranked, and only recipes → [{ kind: 'recipe', entity: {…}, doc: {title: 'Lemon drizzle', body: '3 lemons, 200g butter'}, recipe: {minutes: 50, serves: 8}, rank: {title: 'Lemon drizzle', snip: '3 \x01lemons\x02, 200g butter', score: 2.0000017} }] A word names no component to leave out, so — like `id=` above — a line that is only words answers the WHOLE entity, the app's own components included. That is what lets a page draw cards straight from a search. Name a component beside the word and you are back to the ordinary rule: `lemon&.recipe!` answers recipes with no titles, `lemon&.recipe!&.doc?` answers both. `rank` rides the row for a text query and is never stored. Its `snip` marks the hit with `\x01` and `\x02` so a page can wrap them in whatever it likes — never HTML from the store. Terms match whole tokens: `lemon` does not find `lemons`. A trailing `*` prefix-matches, and quotes make a phrase: await query('lemo*') await query('"coconut milk"') Words and filters mix freely in one line, which is why a search box can hand its whole string to `query()` and a saved filter is a valid search. ## What this store will not do Two pieces of the wider platform grammar are refused here, by name, rather than answered some other way: .doc!&work=build → work lanes are not served by this store .doc!&.order=similar → semantic ranking is not served by this store There is no vector search in an app's store, so `.near=` alone changes nothing about the answer — do not reach for it. Ranking is what a text term gives you. `.kind=` knows the platform's words only (`.kind=task`, `.kind=comment`); your own word is not a kind to it, and `.kind=recipe` is refused. Ask for the component instead — `.recipe!` — which is what you meant. Everything else the grammar has, this store serves. ## A dozen lines that answer something .recipe!&.doc? every recipe, with its title and body .recipe.minutes<=30&.doc? what you can cook in half an hour .recipe.cuisine=thai,vietnamese&.doc? two cuisines at once .doc.title~=lemon&.recipe! recipes whose title says lemon — a substring, not a search, and the title predicate already asked for the doc .chore!&.completed=&.doc? the chores still to do .chore!&.completed.at=today&.doc? the chores done today .chore!&.count! how many chores there are, without listing one .task.status=open&.tally=filed.domain how much open work each part of the house has .reading!&.reading.done=1&.reading.started>=2026-01-01&.doc? books finished since the new year (your own bool is 1, your own time is ISO text) .recipe!&.comments=&.doc? recipes nobody has commented on .doc!&.created.by=&.created!&limit=20 the newest twenty things this person saved, with their stamps id= one entity, whole, however many components it wears The whole guide is at .