InstaQL

Instant provides a GraphQL-like interface for querying. We call our query language InstaQL

Why InstaQL

We like the declarative nature of GraphQL queries but are not fans of a) configuration and b) build steps required to get up and running. To get around a) and b) we built InstaQL using only native javascript arrays and objects.

Fetch namespace

These next sections will use the following sample data:

import { id } from '@instantdb/react'

const workoutId = id()
const proteinId = id()
const sleepId = id()
const standupId = id()
const reviewPRsId = id()
const focusId = id()
const healthId = id()
const workId = id()

transact([
  tx.todos[workoutId].update({ title: 'Go on a run' }),
  tx.todos[proteinId].update({ title: 'Drink protein' }),
  tx.todos[sleepId].update({ title: 'Go to bed early' }),
  tx.todos[standupId].update({ title: 'Do standup' }),
  tx.todos[reviewPRsId].update({ title: 'Review PRs' }),
  tx.todos[focusId].update({ title: 'Code a bunch' }),
  tx.goals[healthId]
    .update({ title: 'Get fit!' })
    .link({ todos: workoutId })
    .link({ todos: proteinId })
    .link({ todos: sleepId }),
  tx.goals[workId]
    .update({ title: 'Get promoted!' })
    .link({ todos: standupId })
    .link({ todos: reviewPRsId })
    .link({ todos: focusId }),
])

Here we have:

• todos, with unique identifiers workoutId, proteinId, sleepId, standupId, reviewPRsId, and focusId
• goals, with unique identifiers healthId and workId
• todos workoutId, proteinId, and sleepId are associated with goal health
• todos standupId, reviewPRsId, and focusId are associated with goal work

One of the simpliest queries you can write is to simply get all entities of a namespace.

const query = { goals: {} }
const { isLoading, error, data } = useQuery(query)

Inspecting data, we'll see:

console.log(data)
{
  "goals": [
    {
      "id": healthId,
      "title": "Get fit!"
    },
    {
      "id": workId,
      "title": "Get promoted!"
    }
  ]
}

For comparison, the SQL equivalent of this would be something like:

const data = { goals: doSQL('SELECT * FROM goals') }

Fetch multiple namespaces

You can fetch multiple namespaces at once:

const query = { goals: {}, todos: {} }
const { isLoading, error, data } = useQuery(query)

We will now see data for both namespaces.

console.log(data)
{
  "goals": [...],
  "todos": [
    {
      "id": focusId,
      "title": "Code a bunch"
    },
    {
      "id": proteinId,
      "title": "Drink protein"
    },
    ...
  ]
}

The equivalent of this in SQL would be to write two separate queries.

const data = {
  goals: doSQL('SELECT * from goals'),
  todos: doSQL('SELECT * from todos'),
}

Fetch a specific entity

If you want to filter entities, you can use the where keyword. Here we fetch a specific goal

const query = {
  goals: {
    $: {
      where: {
        id: 'health',
      },
    },
  },
}
const { isLoading, error, data } = useQuery(query)

console.log(data)
{
  "goals": [
    {
      "id": healthId,
      "title": "Get fit!"
    }
  ]
}

The SQL equivalent would be:

const data = { goals: doSQL("SELECT * FROM goals WHERE id = 'health'") }

Fetch associations

We can fetch goals and their related todos.

const query = {
  goals: {
    todos: {},
  },
}
const { isLoading, error, data } = useQuery(query)

goals would now include nested todos

console.log(data)
{
  "goals": [
    {
      "id": healthId,
      "title": "Get fit!",
      "todos": [...],
    },
    {
      "id": workId,
      "title": "Get promoted!",
      "todos": [...],
    }
  ]
}

Comparing InstaQL vs SQL

The SQL equivalent for this would be something along the lines of:

const query = "
SELECT g.*, gt.todos
FROM goals g
JOIN (
    SELECT g.id, json_agg(t.*) as todos
    FROM goals g
    LEFT JOIN todos t on g.id = t.goal_id
    GROUP BY 1
) gt on g.id = gt.id
"
const data = {goals: doSQL(query)}

Notice the complexity of this SQL query. Although fetching associations in SQL is straightforward via JOIN, marshalling the results in a nested structure via SQL is tricky. An alternative approach would be to write two straight-forward queries and then marshall the data on the client.

const _goals = doSQL("SELECT * from goals")
const _todos = doSQL("SELECT * from todos")
const data = {goals: _goals.map(g => (
  return {...g, todos: _todos.filter(t => t.goal_id === g.id)}
))

Now compare these two approaches with InstaQL

const query = {
  goals: {
    todos: {},
  },
}
const { isLoading, error, data } = useQuery(query)

Modern applications often need to render nested relations, InstaQL really starts to shine for these use cases.

Fetch specific associations

A) Fetch associations for filtered namespace

We can fetch a specific entity in a namespace as well as it's related associations.

const query = {
  goals: {
    $: {
      where: {
        id: 'health',
      },
    },
    todos: {},
  },
}
const { isLoading, error, data } = useQuery(query)

Which returns

console.log(data)
{
  "goals": [
    {
      "id": healthId,
      "title": "Get fit!",
      "todos": [
        {
          "id": proteinId,
          "title": "Drink protein"
        },
        {
          "id": sleepId,
          "title": "Go to bed early"
        },
        {
          "id": workoutId,
          "title": "Go on a run"
        }
      ]
    }
  ]
}

B) Filter namespace by associated values

We can filter namespaces by their associations

const query = {
  goals: {
    $: {
      where: {
        'todos.title': 'Code a bunch',
      },
    },
    todos: {},
  },
}
const { isLoading, error, data } = useQuery(query)

Returns

console.log(data)
{
  "goals": [
    {
      "id": workId,
      "title": "Get promoted!",
      "todos": [
        {
          "id": focusId,
          "title": "Code a bunch"
        },
        {
          "id": reviewPRsId,
          "title": "Review PRs"
        },
        {
          "id": standupId,
          "title": "Do standup"
        }
      ]
    }
  ]
}

C) Filter associations

We can also filter associated data.

const query = {
  goals: {
    $: {
      where: {
        'todos.title': 'Go on a run',
      },
    },
  },
}
const { isLoading, error, data } = useQuery(query)

This will return goals and filtered todos

console.log(data)
{
  "goals": [
    {
      "id": healthId,
      "title": "Get fit!",
      "todos": [
        {
          "id": workoutId,
          "title": "Go on a run"
        }
      ]
    },
    {
      "id": workId,
      "title": "Get promoted!",
      "todos": []
    }
  ]
}

Inverse Associations

Associations are also available in the reverse order.

const query = {
  todos: {
    goals: {},
  },
}
const { isLoading, error, data } = useQuery(query)

console.log(data)
{
  "todos": [
    {
      "id": focusId,
      "title": "Code a bunch",
      "goals": [
        {
          "id": workId,
          "title": "Get promoted!"
        }
      ]
    },
    ...,
  ]
}

More features to come!

We're actively building more features for InstaQL. Let us know on discord if there's a missing feature you'd love for us to add!