useQuery

const {
  data,
  dataUpdatedAt,
  error,
  errorUpdatedAt,
  failureCount,
  failureReason,
  fetchStatus,
  isError,
  isFetched,
  isFetchedAfterMount,
  isFetching,
  isInitialLoading,
  isLoading,
  isLoadingError,
  isPaused,
  isPending,
  isPlaceholderData,
  isRefetchError,
  isRefetching,
  isStale,
  isSuccess,
  refetch,
  status,
} = useQuery(
  () => ({
    queryKey,
    queryFn,
    enabled,
    select,
    placeholderData,
    deferStream,
    reconcile,
    gcTime,
    networkMode,
    initialData,
    initialDataUpdatedAt,
    meta,
    queryKeyHashFn,
    refetchInterval,
    refetchIntervalInBackground,
    refetchOnMount,
    refetchOnReconnect,
    refetchOnWindowFocus,
    retry,
    retryOnMount,
    retryDelay,
    staleTime,
    throwOnError,
  }),
  () => queryClient,
)

const {
  data,
  dataUpdatedAt,
  error,
  errorUpdatedAt,
  failureCount,
  failureReason,
  fetchStatus,
  isError,
  isFetched,
  isFetchedAfterMount,
  isFetching,
  isInitialLoading,
  isLoading,
  isLoadingError,
  isPaused,
  isPending,
  isPlaceholderData,
  isRefetchError,
  isRefetching,
  isStale,
  isSuccess,
  refetch,
  status,
} = useQuery(
  () => ({
    queryKey,
    queryFn,
    enabled,
    select,
    placeholderData,
    deferStream,
    reconcile,
    gcTime,
    networkMode,
    initialData,
    initialDataUpdatedAt,
    meta,
    queryKeyHashFn,
    refetchInterval,
    refetchIntervalInBackground,
    refetchOnMount,
    refetchOnReconnect,
    refetchOnWindowFocus,
    retry,
    retryOnMount,
    retryDelay,
    staleTime,
    throwOnError,
  }),
  () => queryClient,
)

Here are some examples of how to use the useQuery primitive in Solid Query.

The most basic usage of useQuery is to create a query that fetches data from an API.

import { useQuery } from '@tanstack/solid-query'

function App() {
  const todos = useQuery(() => ({
    queryKey: 'todos',
    queryFn: async () => {
      const response = await fetch('/api/todos')
      if (!response.ok) {
        throw new Error('Failed to fetch todos')
      }
      return response.json()
    },
  }))

  return (
    <div>
      <Show when={todos.isError}>
        <div>Error: {todos.error.message}</div>
      </Show>
      <Show when={todos.isLoading}>
        <div>Loading...</div>
      </Show>
      <Show when={todos.isSuccess}>
        <div>
          <div>Todos:</div>
          <ul>
            <For each={todos.data}>{(todo) => <li>{todo.title}</li>}</For>
          </ul>
        </div>
      </Show>
    </div>
  )
}

import { useQuery } from '@tanstack/solid-query'

function App() {
  const todos = useQuery(() => ({
    queryKey: 'todos',
    queryFn: async () => {
      const response = await fetch('/api/todos')
      if (!response.ok) {
        throw new Error('Failed to fetch todos')
      }
      return response.json()
    },
  }))

  return (
    <div>
      <Show when={todos.isError}>
        <div>Error: {todos.error.message}</div>
      </Show>
      <Show when={todos.isLoading}>
        <div>Loading...</div>
      </Show>
      <Show when={todos.isSuccess}>
        <div>
          <div>Todos:</div>
          <ul>
            <For each={todos.data}>{(todo) => <li>{todo.title}</li>}</For>
          </ul>
        </div>
      </Show>
    </div>
  )
}

The reason why useQuery accepts a function that returns an object is to allow for reactive options. This is useful when query options depend on other values/signals that might change over time. Solid Query can track the passed function in a reactive scope and re-run it whenever the dependencies change.

import { useQuery } from '@tanstack/solid-query'

function App() {
  const [filter, setFilter] = createSignal('all')

  const todos = useQuery(() => ({
    queryKey: ['todos', filter()],
    queryFn: async () => {
      const response = await fetch(`/api/todos?filter=${filter()}`)
      if (!response.ok) {
        throw new Error('Failed to fetch todos')
      }
      return response.json()
    },
  }))

  return (
    <div>
      <div>
        <button onClick={() => setFilter('all')}>All</button>
        <button onClick={() => setFilter('active')}>Active</button>
        <button onClick={() => setFilter('completed')}>Completed</button>
      </div>
      <Show when={todos.isError}>
        <div>Error: {todos.error.message}</div>
      </Show>
      <Show when={todos.isLoading}>
        <div>Loading...</div>
      </Show>
      <Show when={todos.isSuccess}>
        <div>
          <div>Todos:</div>
          <ul>
            <For each={todos.data}>{(todo) => <li>{todo.title}</li>}</For>
          </ul>
        </div>
      </Show>
    </div>
  )
}

import { useQuery } from '@tanstack/solid-query'

function App() {
  const [filter, setFilter] = createSignal('all')

  const todos = useQuery(() => ({
    queryKey: ['todos', filter()],
    queryFn: async () => {
      const response = await fetch(`/api/todos?filter=${filter()}`)
      if (!response.ok) {
        throw new Error('Failed to fetch todos')
      }
      return response.json()
    },
  }))

  return (
    <div>
      <div>
        <button onClick={() => setFilter('all')}>All</button>
        <button onClick={() => setFilter('active')}>Active</button>
        <button onClick={() => setFilter('completed')}>Completed</button>
      </div>
      <Show when={todos.isError}>
        <div>Error: {todos.error.message}</div>
      </Show>
      <Show when={todos.isLoading}>
        <div>Loading...</div>
      </Show>
      <Show when={todos.isSuccess}>
        <div>
          <div>Todos:</div>
          <ul>
            <For each={todos.data}>{(todo) => <li>{todo.title}</li>}</For>
          </ul>
        </div>
      </Show>
    </div>
  )
}

useQuery supports triggering SolidJS Suspense and ErrorBoundary components when the query is in a pending or error state. This allows you to easily handle loading and error states in your components.

import { useQuery } from '@tanstack/solid-query'

function App() {
  const todos = useQuery(() => ({
    queryKey: 'todos',
    queryFn: async () => {
      const response = await fetch('/api/todos')
      if (!response.ok) {
        throw new Error('Failed to fetch todos')
      }
      return response.json()
    },
    throwOnError: true,
  }))

  return (
    <ErrorBoundary fallback={<div>Error: {todos.error.message}</div>}>
      <Suspense fallback={<div>Loading...</div>}>
        <div>
          <div>Todos:</div>
          <ul>
            <For each={todos.data}>{(todo) => <li>{todo.title}</li>}</For>
          </ul>
        </div>
      </Suspense>
    </ErrorBoundary>
  )
}

import { useQuery } from '@tanstack/solid-query'

function App() {
  const todos = useQuery(() => ({
    queryKey: 'todos',
    queryFn: async () => {
      const response = await fetch('/api/todos')
      if (!response.ok) {
        throw new Error('Failed to fetch todos')
      }
      return response.json()
    },
    throwOnError: true,
  }))

  return (
    <ErrorBoundary fallback={<div>Error: {todos.error.message}</div>}>
      <Suspense fallback={<div>Loading...</div>}>
        <div>
          <div>Todos:</div>
          <ul>
            <For each={todos.data}>{(todo) => <li>{todo.title}</li>}</For>
          </ul>
        </div>
      </Suspense>
    </ErrorBoundary>
  )
}

• Query Options - Accessor<QueryOptions>

  • queryKey: unknown[]

    • Required
    • The query key to use for this query.
    • The query key will be hashed into a stable hash. See Query Keys for more information.
    • The query will automatically update when this key changes (as long as enabled is not set to false).

  • queryFn: (context: QueryFunctionContext) => Promise<TData>

    • Required, but only if no default query function has been defined See Default Query Function for more information.
    • The function that the query will use to request data.
    • Receives a QueryFunctionContext
    • Must return a promise that will either resolve data or throw an error. The data cannot be undefined.

  • enabled: boolean

    • Set this to false to disable this query from automatically running.
    • Can be used for Dependent Queries for more information.

  • select: (data: TData) => unknown

    • Optional
    • This option can be used to transform or select a part of the data returned by the query function. It affects the returned data value, but does not affect what gets stored in the query cache.
    • The select function will only run if data changed, or if the reference to the select function itself changes. To optimize, wrap the function in useCallback.

  • placeholderData: TData | (previousValue: TData | undefined; previousQuery: Query | undefined,) => TData

    • Optional
    • If set, this value will be used as the placeholder data for this particular query observer while the query is still in the pending state.
    • placeholderData is not persisted to the cache
    • If you provide a function for placeholderData, as a first argument you will receive previously watched query data if available, and the second argument will be the complete previousQuery instance.

  • deferStream: boolean

    • Optional
    • Defaults to false
    • Only applicable while rendering queries on the server with streaming.
    • Set deferStream to true to wait for the query to resolve on the server before flushing the stream.
    • This can be useful to avoid sending a loading state to the client before the query has resolved.

  • reconcile: false | string | ((oldData: TData | undefined, newData: TData) => TData)

    • Optional
    • Defaults to false
    • Set this to a string to enable reconciliation between query results based on the string key.
    • Set this to a function which accepts the old and new data and returns resolved data of the same type to implement custom reconciliation logic.

  • gcTime: number | Infinity

    • Defaults to 5 * 60 * 1000 (5 minutes) or Infinity during SSR
    • The time in milliseconds that unused/inactive cache data remains in memory. When a query's cache becomes unused or inactive, that cache data will be garbage collected after this duration. When different garbage collection times are specified, the longest one will be used.
    • Note: the maximum allowed time is about 24 days, although it is possible to work around this limit using timeoutManager.setTimeoutProvider.
    • If set to Infinity, will disable garbage collection

  • networkMode: 'online' | 'always' | 'offlineFirst'

    • optional
    • defaults to 'online'
    • see Network Mode for more information.

  • initialData: TData | () => TData

    • Optional
    • If set, this value will be used as the initial data for the query cache (as long as the query hasn't been created or cached yet)
    • If set to a function, the function will be called once during the shared/root query initialization, and be expected to synchronously return the initialData
    • Initial data is considered stale by default unless a staleTime has been set.
    • initialData is persisted to the cache

  • initialDataUpdatedAt: number | (() => number | undefined)

    • Optional
    • If set, this value will be used as the time (in milliseconds) of when the initialData itself was last updated.

  • meta: Record<string, unknown>

    • Optional
    • If set, stores additional information on the query cache entry that can be used as needed. It will be accessible wherever the query is available, and is also part of the QueryFunctionContext provided to the queryFn.

  • queryKeyHashFn: (queryKey: QueryKey) => string

    • Optional
    • If specified, this function is used to hash the queryKey to a string.

  • refetchInterval: number | false | ((query: Query) => number | false | undefined)

    • Optional
    • If set to a number, all queries will continuously refetch at this frequency in milliseconds
    • If set to a function, the function will be executed with the query to compute a frequency

  • refetchIntervalInBackground: boolean

    • Optional
    • If set to true, queries that are set to continuously refetch with a refetchInterval will continue to refetch while their tab/window is in the background

  • refetchOnMount: boolean | "always" | ((query: Query) => boolean | "always")

    • Optional
    • Defaults to true
    • If set to true, the query will refetch on mount if the data is stale.
    • If set to false, the query will not refetch on mount.
    • If set to "always", the query will always refetch on mount.
    • If set to a function, the function will be executed with the query to compute the value

  • refetchOnWindowFocus: boolean | "always" | ((query: Query) => boolean | "always")

    • Optional
    • Defaults to true
    • If set to true, the query will refetch on window focus if the data is stale.
    • If set to false, the query will not refetch on window focus.
    • If set to "always", the query will always refetch on window focus.
    • If set to a function, the function will be executed with the query to compute the value

  • refetchOnReconnect: boolean | "always" | ((query: Query) => boolean | "always")

    • Optional
    • Defaults to true
    • If set to true, the query will refetch on reconnect if the data is stale.
    • If set to false, the query will not refetch on reconnect.
    • If set to "always", the query will always refetch on reconnect.
    • If set to a function, the function will be executed with the query to compute the value

  • retry: boolean | number | (failureCount: number, error: TError) => boolean

    • If false, failed queries will not retry by default.
    • If true, failed queries will retry infinitely.
    • If set to a number, e.g. 3, failed queries will retry until the failed query count meets that number.
    • defaults to 3 on the client and 0 on the server

  • retryOnMount: boolean

    • If set to false, the query will not be retried on mount if it contains an error. Defaults to true.

  • retryDelay: number | (retryAttempt: number, error: TError) => number

    • This function receives a retryAttempt integer and the actual Error and returns the delay to apply before the next attempt in milliseconds.
    • A function like attempt => Math.min(attempt > 1 ? 2 ** attempt * 1000 : 1000, 30 * 1000) applies exponential backoff.
    • A function like attempt => attempt * 1000 applies linear backoff.

  • staleTime: number | Infinity

    • Optional
    • Defaults to 0
    • The time in milliseconds after data is considered stale. This value only applies to the hook it is defined on.
    • If set to Infinity, the data will never be considered stale

  • throwOnError: undefined | boolean | (error: TError, query: Query) => boolean

    • Set this to true if you want errors to be thrown in the render phase and propagate to the nearest error boundary
    • Set this to false to disable suspense's default behavior of throwing errors to the error boundary.
    • If set to a function, it will be passed the error and the query, and it should return a boolean indicating whether to show the error in an error boundary (true) or return the error as state (false)

• Query Client - Accessor<QueryClient>

  • Optional
  • Use this to use a custom QueryClient. Otherwise, the one from the nearest context will be used.

useQuery returns a SolidJS store with the following properties:

• status: QueryStatus

  • Will be:
    • pending if there's no cached data and no query attempt was finished yet.
    • error if the query attempt resulted in an error. The corresponding error property has the error received from the attempted fetch
    • success if the query has received a response with no errors and is ready to display its data. The corresponding data property on the query is the data received from the successful fetch or if the query's enabled property is set to false and has not been fetched yet data is the first initialData supplied to the query on initialization.

• isPending: boolean

  • A derived boolean from the status variable above, provided for convenience.

• isSuccess: boolean

  • A derived boolean from the status variable above, provided for convenience.

• isError: boolean

  • A derived boolean from the status variable above, provided for convenience.

• isLoadingError: boolean

  • Will be true if the query failed while fetching for the first time.

• isRefetchError: boolean

  • Will be true if the query failed while refetching.

• data: Resource<TData>

  • Defaults to undefined.
  • The last successfully resolved data for the query.
  • Important: The data property is a SolidJS resource. This means that if the data is accessed underneath a <Suspense> component, it will trigger the Suspense boundary if the data is not available yet.

• dataUpdatedAt: number

  • The timestamp for when the query most recently returned the status as "success".

• error: null | TError

  • Defaults to null
  • The error object for the query, if an error was thrown.

• errorUpdatedAt: number

  • The timestamp for when the query most recently returned the status as "error".

• isStale: boolean

  • Will be true if the data in the cache is invalidated or if the data is older than the given staleTime.

• isPlaceholderData: boolean

  • Will be true if the data shown is the placeholder data.

• isFetched: boolean

  • Will be true if the query has been fetched.

• isFetchedAfterMount: boolean

  • Will be true if the query has been fetched after the component mounted.
  • This property can be used to not show any previously cached data.

• fetchStatus: FetchStatus

  • fetching: Is true whenever the queryFn is executing, which includes initial pending as well as background refetches.
  • paused: The query wanted to fetch, but has been paused.
  • idle: The query is not fetching.
  • see Network Mode for more information.

• isFetching: boolean

  • A derived boolean from the fetchStatus variable above, provided for convenience.

• isPaused: boolean

  • A derived boolean from the fetchStatus variable above, provided for convenience.

• isRefetching: boolean

  • Is true whenever a background refetch is in-flight, which does not include initial pending
  • Is the same as isFetching && !isPending

• isLoading: boolean

  • Is true whenever the first fetch for a query is in-flight
  • Is the same as isFetching && isPending

• isInitialLoading: boolean

  • deprecated
  • An alias for isLoading, will be removed in the next major version.

• failureCount: number

  • The failure count for the query.
  • Incremented every time the query fails.
  • Reset to 0 when the query succeeds.

• failureReason: null | TError

  • The failure reason for the query retry.
  • Reset to null when the query succeeds.

• errorUpdateCount: number

  • The sum of all errors.

• refetch: (options: { throwOnError: boolean, cancelRefetch: boolean }) => Promise<UseQueryResult>

  • A function to manually refetch the query.
  • If the query errors, the error will only be logged. If you want an error to be thrown, pass the throwOnError: true option
  • cancelRefetch?: boolean
    • Defaults to true
      • Per default, a currently running request will be cancelled before a new request is made
    • When set to false, no refetch will be made if there is already a request running.