Struct Client

pub struct Client { /* private fields */ }

A database connection client.

This is the struct used to interact with the database. Typically, you will use the connect() function to create this struct, or with a Builder that you pass to Client::new().

Implementations

impl Client

pub fn new(builder: Config) -> Client

Create a new connection pool.

Note this does not create a connection immediately. Use ensure_connected() to establish a connection and verify that the connection is usable.

pub async fn close(&self)

Start shutting down the connection pool.

Note that this waits for all connections to be released when called for the first time. But if it is called multiple times concurrently, only the first call will wait and subsequent call will exit immediately.

pub async fn ensure_connected(&self) -> Result<(), Error>

Ensure that there is at least one working connection to the pool.

This can be used at application startup to ensure that you have a working connection.

pub async fn query<R, A>( &self, request: &str, arguments: &A, ) -> Result<Vec<R>, Error>

where A: QueryArgs, R: QueryResult,

Execute a query and return a collection of results.

You will usually have to specify the return type for the query:

let greeting = pool.query::<String, _>("SELECT 'hello'", &());
// or
let greeting: Vec<String> = pool.query("SELECT 'hello'", &());

This method can be used with both static arguments, like a tuple of scalars, and with dynamic arguments edgedb_protocol::value::Value. Similarly, dynamically typed results are also supported.

pub async fn query_single<R, A>( &self, request: &str, arguments: &A, ) -> Result<R, Error>

where A: QueryArgs, R: QueryResult,

Execute a query and return a single result.

You will usually have to specify the return type for the query:

let greeting = pool.query_single::<String, _>("SELECT 'hello'", &());
// or
let greeting: String = pool.query_single("SELECT 'hello'", &());

The query must return exactly one element. If the query returns more than one element, a ResultCardinalityMismatchError is raised. If the query returns an empty set, a NoDataError is raised.

This method can be used with both static arguments, like a tuple of scalars, and with dynamic arguments edgedb_protocol::value::Value. Similarly, dynamically typed results are also supported.

pub async fn query_json<A>( &self, request: &str, arguments: &A, ) -> Result<Json, Error>

where A: QueryArgs,

Execute a query and return the result as JSON.

pub async fn query_single_json<A>( &self, request: &str, arguments: &A, ) -> Result<Json, Error>

where A: QueryArgs,

Execute a query and return a single result as JSON.

The query must return exactly one element. If the query returns more than one element, a ResultCardinalityMismatchError is raised. If the query returns an empty set, a NoDataError is raised.

pub async fn execute<A>( &self, request: &str, arguments: &A, ) -> Result<ExecuteResult, Error>

where A: QueryArgs,

Execute one or more EdgeQL commands.

Note that if you want the results of query, use query() or query_single() instead.

Trait Implementations

impl Clone for Client

fn clone(&self) -> Client

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Client

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Executor for Client