Get()

即将作废

This method gets entities by their IDs.

func (c *GrpcClient) Get(ctx context.Context, collectionName string, ids entity.Column, opts ...GetOption) (ResultSet, error)

Parameter	Description	Type
ctx	Context for the current call to work.	context.Context
collectionName	Name of a collection.	string
ids	Boolean expression for metadata filtering. For details, refer to Scalar Filtering Rules.	entity.Column
opts	Extra query options. You can add multiple client.GetOption instances.	...[client.GetOption](./v1-Collection-Get#clientgetoption)

client.GetOption

You can add extra settings to the Get() request using the following methods.

Method	Description
GetWithOutputFields(outputFields ...string)	Sets the names of fields to be included in the return.
GetWithPartitions(partitionNames ...string)	Restricts the query within the specified partitions.

A client.ResultSet, which is a slice of entity.Column.

client.ResultSet

The client.ResultSet provides the following methods for you to manipulate the query results.

Method	Return Type	Description
GetColumn(fieldName string)	entity.Column	Return the column with the provided name.
Len()	int	Return the number of entities in the query result.
Slice(start, end int)	client.ResultSet	Return a slice of the query result.

Errors

Any error in the execution of the request. Possible errors are as follows:

• ErrClientNotReady: The client is not connected to Milvus.

• ErrCollectionNotExists: The collection with the specified name does not exist.

• The call to this API fails.

Example

// get
ids := entity.NewColumnInt64("id", []int64{10, 11, 12, 19})
queryRes, errQuery := mc.Get(context.Background(), collectionName, ids, client.GetWithOutputFields("varchar"))
if errQuery != nil {
   log.Fatal("failed to query collection:", errQuery.Error())
}
for _, res := range queryRes {
   log.Println(res.Name(), res.FieldData())
}