Java Module java.sql Package java.sql Interface ShardingKey（JDK11）

public interface ShardingKey

Interface used to indicate that this object represents a Sharding Key. A ShardingKey instance is only guaranteed to be compatible with the data source instance that it was derived from. A ShardingKey is created using ShardingKeyBuilder.

The following example illustrates the use of ShardingKeyBuilder to create a ShardingKey:

 

     DataSource ds = new MyDataSource();
     ShardingKey shardingKey = ds.createShardingKeyBuilder()
                           .subkey("abc", JDBCType.VARCHAR)
                           .subkey(94002, JDBCType.INTEGER)
                           .build();
 
 

A ShardingKey may also be used for specifying a superShardingKey. Databases that support composite Sharding may use a superShardingKey to specify a additional level of partitioning within the Shard.

The following example illustrates the use of ShardingKeyBuilder to create a superShardingKey for an eastern region with a ShardingKey specified for the Pittsburgh branch office:

 

     DataSource ds = new MyDataSource();
     ShardingKey superShardingKey = ds.createShardingKeyBuilder()
                           .subkey("EASTERN_REGION", JDBCType.VARCHAR)
                           .build();
     ShardingKey shardingKey = ds.createShardingKeyBuilder()
                           .subkey("PITTSBURGH_BRANCH", JDBCType.VARCHAR)
                           .build();
     Connection con = ds.createConnectionBuilder()
                           .superShardingKey(superShardingKey)
                           .shardingKey(shardingKey)
                           .build();