`db`: the rows of the app, in code

A function written with run is handed db: the tables of the project, each by its name, under the rules of the caller.

TypeScript

export const orderOf = query('orderOf', {
  access: 'signedIn',
  input: { id: text() },
  run: ({ input, db }) => db.orders.get(input.id),
})

What it is handed, and where

In the `run` of	`db`	Answers
a query	reads	at once: no `await`, and the `run` is not `async`
a change	reads and writes	at once: no `await`, and the `run` is not `async`
an action	reads	a promise: each read is awaited, `await db.orders.get(id)`. An action writes by calling a change
the arrow of a seed	reads and writes, with full access	at once

A query and a change answer at once because each is one reading or one write of the data, with nothing waited for in the middle. An await there, or an async run, is code.T4005.

Reading

db.<table> has the members of a plan (topic.plans): where, search, near, group, with, pick, newest, oldest, sort, limit, skip, after. A plan in code is ended by the member that carries it out:

Member	Answers
`.all()`	The rows, as a list
`.first()`	The first row, or nothing
`.count()`	A number
`db.<table>.get(id)`	The row of that id, or nothing. It needs no end
`db.<table>.count(filter)`	A number
`db.<table>.history(id)`	Each state the row had

A plan that is not ended is no rows, and the type checker says so in many words. tent check then reports code.T8000 with TS2740 or TS2322, of a type DbChain<...> that "is missing the following properties from type 'readonly unknown[]'", often at the screen that reads the query and not at the query. What it means: write .all() or .first() at the end of the plan.

A row is handed as code holds it: a date is a Date, a link is the id of the linked row as text, and with .with('customer') the linked row itself.

Writing

In a change and in the arrow of a seed:

TypeScript

const order = db.orders.add({ customer: input.customer, total: input.total })
db.orders.change(order.id, { status: 'paid' })
db.orders.remove(order.id)

add and change answer the row as it is after the write, with its id, createdAt and updatedAt. A value that is left out takes the default of its column, and null clears a column.

The rules of the caller, and `db.system`

db reads and writes as the caller of the function: the access of each table holds, so a caller is answered the rows they may read and nothing else, and a write they may not make fails with code.T3101.

db.system is the same tables with full access: every row, whatever the rules say. A function may use it only where it states system: 'why', a text that says why it needs every row (option.query.system); without that, tent check reports code.T3004. db beside it stays limited to the caller.

TypeScript

export const ordersOfTheDay = query('ordersOfTheDay', {
  access: role('staff'),
  system: 'the staff see the orders of every customer',
  run: ({ db }) => db.system.orders.where({ status: 'open' }).with('customer').all(),
})

db: the rows of the app, in code

What it is handed, and where

Reading

Writing

The rules of the caller, and db.system

See also

`db`: the rows of the app, in code

The rules of the caller, and `db.system`