Query()

Queries a collection with a scalar filter and returns the matching entities.

pub async fn query(&self, request: QueryRequest) -> Result<QueryResponse>

Request Syntax

let request = QueryRequest::builder()
    .collection_name("books")
    .filter("id > 0")
    .output_fields(["id", "title"])
    .limit(10)
    .build()?;

REQUEST FIELDS:

• database_name: Option<String>

  Name of the target database; uses the default database when empty.

• collection_name: String

  Name of the collection to query. Required.

• partition_names: Vec<String>

  Partition names to restrict the query to; queries the whole collection when empty.

• ids: Ids

  Primary keys of the entities to retrieve. Mutually exclusive with filter. See Ids.

• filter: String

  Scalar filter expression that selects the entities. Mutually exclusive with ids.

• filter_templates: HashMap<String, Value>

  Placeholder values referenced by the filter expression.

• output_fields: Vec<String>

  Names of the fields returned for each row.

• limit: Option<i64>

  Maximum number of rows to return. None returns all matching rows.

• offset: Option<i64>

  Number of leading rows to skip.

• ignore_growing: bool

  Whether to ignore growing segments during the query. Defaults to false.

• timezone: String

  Timezone applied when querying or filtering Timestamptz fields.

• consistency_level: Option<ConsistencyLevel>

  Consistency guarantee for the query; the collection default is used when unset. See ConsistencyLevel.

• extra_params: HashMap<String, String>

  Additional query parameters.

RETURN TYPE:

Result

RETURNS:

A QueryResponse containing the rows matched by the query. Returns an Error if the operation fails.

QueryResponse
    results() // -> &QueryResults
    session_timestamp() // -> u64

METHODS:

• results() (&QueryResults) -

  The rows matched by the query.

  • get_output_fields() (&[FieldData]) -

    The output field values of the returned rows. See FieldData.

  • get_output_field_names() (&[String]) -

    The names of the output fields.

  • get_output_field() (Option<&FieldData>) -

    The value of the named output field for the returned rows, when present. See FieldData.

  • get_row_count() (u64) -

    The number of rows returned.

  • is_empty() (bool) -

    Whether no rows were returned.

  • get_output_rows() (Result>) -

    The returned rows as entity values. See EntityRow.

  • get_output_row() (Result) -

    The row at the given index as an entity value. See EntityRow.

• session_timestamp() (u64) -

  The session timestamp of the query.

Example

let request = QueryRequest::builder()
    .collection_name("books")
    .filter("id > 0")
    .output_fields(["id", "title"])
    .limit(10)
    .build()?;
let resp = client.query(request).await?;