Struct qldb::QueryBuilder [−][src]
pub struct QueryBuilder { /* fields omitted */ }
Expand description
Represents the query being built. It allows to add parameters and to execute the query.
Implementations
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 ?
.
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.
This method will automatically load all the pages. It may require to make several HTTP calls to the QLDB Ledger as each Page contains no more than 200 documents.
It consumes the QueryBuilder in the process.
Creates a cursor for this query, allowing to load values page by page. Each page in QLDB contains 200 documents.
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
It consumes the QueryBuilder in the process.
Trait Implementations
Auto Trait Implementations
impl !RefUnwindSafe for QueryBuilder
impl Send for QueryBuilder
impl Sync for QueryBuilder
impl Unpin for QueryBuilder
impl !UnwindSafe for QueryBuilder