public HiveTableScan copy(RelDataType newRowtype) {
    return new HiveTableScan(getCluster(), getTraitSet(), ((RelOptHiveTable) table), this.tblAlias,
        this.concatQbIDAlias, newRowtype, this.useQBIdInDigest, this.insideView, this.tableScanTrait);
  }
Copy TableScan operator with a new Row Schema. The new Row Schema can only
be a subset of this TS schema.

@param newRowtype
@return
ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/reloperators/HiveTableScan.java