db - Hyperwisor

The db global reads and writes records in the product’s database. Both methods are asynchronous (they return Promises).

Query

const rows = await db.query(tableName, filters?, options?);

string

required

The table to read from.

object

Field filters — plain values for equality, or an operator object (see below).

object

{ limit?, offset?, orderBy?, ascending? }. Without orderBy, results come back newest-first (created_at descending).

const recent = await db.query('readings',
  { device: 'pump-1' },
  { limit: 20, orderBy: 'created_at', ascending: false }
);

Filter operators

A filter value can be an operator object instead of a plain value — for range and comparison queries:

// All readings with temp >= 25
const hot = await db.query('sensor_readings', { temp: { gte: 25 } }, { limit: 10 });

// A range: 20 <= temp < 30
const mild = await db.query('sensor_readings', { temp: { gte: 20, lt: 30 } });

// Equality is just a plain value
const pump1 = await db.query('readings', { device: 'pump-1' });

Operator	Meaning
`gte` / `gt`	greater than or equal / greater than
`lte` / `lt`	less than or equal / less than
`eq` / `neq`	equal / not equal

Multiple operators on one field combine (AND), and multiple fields combine (AND).

Insert

const created = await db.insert(tableName, data);

await db.insert('readings', { device: 'pump-1', temperature: 27.4 });

Example — render the latest reading

const rows = await db.query('readings', {}, { limit: 1, orderBy: 'created_at', ascending: false });
if (rows.length) {
  widget.setText('lastReading', `${rows[0].temperature} °C`);
}

Next: location

Read device geolocation.

​Query

​Filter operators

​Insert

​Example — render the latest reading

Next: location

Query

Filter operators

Insert

Example — render the latest reading