Options copyIndex(int copyIndex) {
      assert copyIndex >= 0;
      this.copyIndex = copyIndex;
      return this;
    }
{@link OrcRawRecordMerger} Acid reader is used slightly differently in various contexts.
This makes the "context" explicit.
ql/src/java/org/apache/hadoop/hive/ql/io/orc/OrcRawRecordMerger.java