Bin operations
Jump to the Code block for a combined complete example.
Setup
The following examples will use the setup and record below to illustrate single record command operations in an Aerospike database.
import com.aerospike.client.AerospikeClient;
import com.aerospike.client.Bin;
import com.aerospike.client.Key;
import com.aerospike.client.Record;
import com.aerospike.client.Value;
import com.aerospike.client.Operation;
import com.aerospike.client.cdt.MapOrder;
import com.aerospike.client.cdt.MapWriteFlags;
import com.aerospike.client.cdt.MapPolicy;
import com.aerospike.client.cdt.MapOperation;
// Establishes a connection to the server
AerospikeClient client = new AerospikeClient("127.0.0.1", 3000);
// Creates a key with the namespace "sandbox", set "ufodata", and user key 5001
Key key = new Key("sandbox", "ufodata", 5001);
The record structure:
+------+----------+----------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------+
| PK | occurred | reported | report | location |
+------+----------+----------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------+
| 5001 | 20220531 | 20220601 | MAP('{"shape":["circle", "flash", "disc"], "summary":"Large flying disc flashed in the sky above the student union. Craziest thing I've ever seen!", "city":"Ann Arbor", "state":"Michigan", "duration":"5 minutes"}') | GeoJSON('{"type":"Point","coordinates":[42.2808,83.743]}') |
+------+----------+----------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------+
Operations
Use the Aerospike Client API to perform separate operations on one or multiple bins in a record within a single transaction. This feature performs an atomic modification then returns the result. The table below shows some of the bin operations available for operate transactions.
Operations for List, Map, Blob/Bytes, Geospatial, and HyperLogLog data types can be found here.
| Data Type | Operation | Description |
|---|---|---|
| All | op_put | Upsert (create or update) a bin. Also called write. |
| All | op_get | Read a bin. Also called read. |
| All | op_touch | Increase the generation counter for a record. |
| All | op_delete | Remove a record from the database. |
| Integer Float | op_add | Add (or subtract) a value. Used to implement counters. Also called increment. |
| String | op_append op_prepend | Modify a string. |
Operations are performed in user defined order.
Single operation
All of the operations in the table above, along with CDT, Blob/Bytes, Geospatial, and HyperLogLog operations,
can be executed as a single operation with the operate method.
The following example creates a map policy for a KEY_ORDERED map, then applies that policy to the report bin. A KEY_ORDERED map provides faster access than the default UNORDERED map. This example passes null to use the default policy,
but a write policy could be passed instead.
// Create KEY_ORDERED map policy
MapPolicy mapPolicy = new MapPolicy(MapOrder.KEY_ORDERED, MapWriteFlags.DEFAULT);
// Update the record
client.operate(null, key, MapOperation.setMapPolicy(mapPolicy, "report"));
// Close the connection to the server
client.close();
Multiple Operations
Multiple operations can be combined in a single transaction when one or more bins need to be updated or read.
The following example inserts the posted bin with value 20220602, updates the city inside the report bin to "Ypsilanti", and reads the report bin in a single transaction.
// Create posted bin to insert
Bin posted = new Bin("posted", 20220602);
// Update the record
Record record = client.operate(null, key,
Operation.put(posted),
MapOperation.put(MapPolicy.Default, "report", Value.get("city"), Value.get("Ypsilanti")),
Operation.get("report")
);
// Do something
System.out.format("Record: %s\\n", record.bins);
// Close the connection to the server
client.close();
Returning from operate()
It's important to understand how the operate method returns data, since operate accepts a variety of operations and deals with both reads and writes in a single call.
Examples of operations and results:
- A basic
putorwriteoperation does not return anything by default, though it can be set to returnnullthrough a write policy. - A map or list
modifyoperation returns the map or list size for thebin_name. - A
getorreadoperation returns the value for thebin_name.
See Bitwise Operations, List Operations, Map Operations, HLL Operations, and Expressions for more information about return values.
The operate method takes the results of all the operations executed within the call and groups them together by bin_name.
If a specific bin_name has multiple results, such as an operate call containing multiple operations that return results for a single bin_name, a list is created containing the results of each operation.
If a bin_name has a single value, the bin_name value is returned as expected.
When grouped by bin_name, the way results are accessed will vary based on what operations are performed.
Some types of write commands do not return results
by default, which can make it difficult to determine the correct result offset.
To ensure that every write command returns a result, set the
WritePolicy.respondAllOps field to true.