Merge `TIME_BUCKET` of `Metrics` and `Record` into `StorageData` (#10208)

docs/en/changes/changes.md

@@ -63,6 +63,7 @@
 * Fix the meter value are not correct when using `sumPerMinLabeld` or `sumHistogramPercentile` MAL function.
 * Fix cannot display attached events when using Zipkin Lens UI query traces.
 * Remove `time_bucket` for both Stream and Measure kinds in BanyanDB plugin.
+* Merge `TIME_BUCKET` of `Metrics` and `Record` into `StorageData`.
 
 #### UI
 

oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/analysis/metrics/Metrics.java

@@ -41,8 +41,6 @@ import static org.apache.skywalking.oap.server.core.analysis.metrics.Metrics.ID;
 })
 @SQLDatabase.Sharding(shardingAlgorithm = ShardingAlgorithm.TIME_RELATIVE_ID_SHARDING_ALGORITHM, tableShardingColumn = ID, dataSourceShardingColumn = ENTITY_ID)
 public abstract class Metrics extends StreamData implements StorageData {
-
-    public static final String TIME_BUCKET = "time_bucket";
     public static final String ENTITY_ID = "entity_id";
     public static final String ID = "id";
 
@@ -55,7 +53,8 @@ public abstract class Metrics extends StreamData implements StorageData {
     private long timeBucket;
 
     /**
-     * Time in the cache, only work when MetricsPersistentWorker#enableDatabaseSession == true.
+     * The last update timestamp of the cache.
+     * The `update` means it is combined with the new metrics. This update doesn't mean the database level update ultimately.
      */
     @Getter
     private long lastUpdateTimestamp = 0L;

oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/analysis/record/Record.java

@@ -29,9 +29,6 @@ import org.apache.skywalking.oap.server.core.storage.annotation.Column;
  * original log data or task records. These data needs to persistent without further analysis.
  */
 public abstract class Record implements StorageData {
-
-    public static final String TIME_BUCKET = "time_bucket";
-
     /**
      * Time attribute, all storage data is time sensitive, as same as {@link Metrics}
      */

oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/remote/data/StreamData.java

@@ -21,6 +21,10 @@ package org.apache.skywalking.oap.server.core.remote.data;
 import org.apache.skywalking.oap.server.core.remote.Deserializable;
 import org.apache.skywalking.oap.server.core.remote.Serializable;
 
+/**
+ * StreamData indicates all implementations supporting {@link Serializable}, {@link Deserializable} and remote hashcode
+ * to do L1 and L2 aggregation cross OAP nodes.
+ */
 public abstract class StreamData implements Serializable, Deserializable {
     public abstract int remoteHashCode();
 }

oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/storage/StorageData.java

@@ -22,6 +22,8 @@ package org.apache.skywalking.oap.server.core.storage;
  * Any persistent entity should be an implementation of this interface.
  */
 public interface StorageData {
+    String TIME_BUCKET = "time_bucket";
+
     /**
      * @return the unique id used in any storage option.
      */