public String[] getScratchColumnTypeNames() {
    String[] result = new String[ocm.outputColCount];
    for (int i = 0; i < ocm.outputColCount; i++) {
      String vectorTypeName = ocm.scratchVectorTypeNames[i];
      String typeName;
      if (vectorTypeName.equalsIgnoreCase("bytes")) {
        // Use hive type name.
        typeName = serdeConstants.STRING_TYPE_NAME;
      } else if (vectorTypeName.equalsIgnoreCase("long")) {
        // Use hive type name.
        typeName = serdeConstants.BIGINT_TYPE_NAME;
      } else {
        typeName = vectorTypeName;
      }
      result[i] =  typeName;
    }
    return result;
  }
Invoke special handling for expressions that can't be vectorized by regular
descriptor based lookup.
ql/src/java/org/apache/hadoop/hive/ql/exec/vector/VectorizationContext.java