Struct qldb::QueryBuilder

pub struct QueryBuilder { /* fields omitted */ }

Represents the query being built. It allows to add parameters and to execute the query.

Implementations

impl QueryBuilder

pub fn param<P: Into<IonValue> + Clone>(&mut self, param: P) -> &mut Self

Adds a param to the query. Params in PartiQL are deoned by the character ?. For example, the query: SELECT * FROM Autos WHERE id = ? AND model = ? will need 2 calls to this method. The first will refer to the first ? and the second to the second ?.

pub async fn execute<'_>(&'_ mut self) -> QLDBResult<Vec<IonValue>>

Executes the query in QLDBwith the parameter provided by the param method. It will return a Vector of Ion Values, one for each document returned.

pub async fn count<'_>(&'_ mut self) -> QLDBResult<i64>

Sends a query to QLDB that returns a count. Keep in mind that there isn't any filter to fail is another kind of statement is given.

Be careful with COUNT statements as they "block" the whole table and other transactions affecting the same table will return an OCC error when committed.

If you want to make a simple count, it is better to use the count method from Client::count

Trait Implementations

impl Clone for QueryBuilder

pub fn clone(&self) -> QueryBuilder

Returns a copy of the value.

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

Performs copy-assignment from source.