private VectorizedRowBatch getVectorizedRowBatchStringLong(byte[] vector, int start, int length) {
    VectorizedRowBatch batch = new VectorizedRowBatch(2, 1);
    BytesColumnVector bcv = new BytesColumnVector(1);

    bcv.vector[0] = vector;
    bcv.start[0] = start;
    bcv.length[0] = length;

    batch.cols[0] = bcv;
    batch.cols[1] = new LongColumnVector(1);
    batch.size = 1;
    return batch;
  }
Input array is used to fill the entire size of the vector row batch
ql/src/test/org/apache/hadoop/hive/ql/exec/vector/expressions/TestVectorTimestampExpressions.java