@Override
      public void apply(SerDeInfo t, Object[] fields) {
        t.putToParameters((String)fields[1], extractSqlClob(fields[2]));
      }
Merges applies the result of a PM SQL query into a tree of object.
Essentially it's an object join. DN could do this for us, but it issues queries
separately for every object, which is suboptimal.
@param pm
@param tree The object tree, by ID.
@param queryText The query text.
@param keyIndex Index of the Long column corresponding to the map ID in query result rows.
@param func The function that is called on each (object,row) pair with the same id.
@return the count of results returned from the query.
standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/MetastoreDirectSqlUtils.java