@Override
  public String vectorExpressionParameters() {
    return getColumnParamString(0, inputColumnNum[0]) + ", val " + displayUtf8Bytes(value);
  }
Vectorized instruction to concatenate a string column to a scalar and put
the result in an output column.
ql/src/java/org/apache/hadoop/hive/ql/exec/vector/expressions/StringGroupColConcatStringScalar.java