@Override protected PropertySchema schemaOf(String[] keys) {
    return keys.length > 0 && keys.length < SCHEMAS.length? SCHEMAS[keys.length - 1] : TABLE_SCHEMA;
  }
Determines the schema from the property name fragments.
<p>The number of fragments is enough to determine if we are dealing with cluster (1 fragment, the
property name), database (2 fragments, 1 for db name, 2 for property), table (3 fragments, db name;,
table name, property name).</p>
@param keys the property key fragments
@return the schema
standalone-metastore/metastore-common/src/main/java/org/apache/hadoop/hive/metastore/properties/HMSPropertyManager.java