org.apache.hadoop.hive.ql.exec
Class TableScanOperator
java.lang.Object
org.apache.hadoop.hive.ql.exec.Operator<TableScanDesc>
org.apache.hadoop.hive.ql.exec.TableScanOperator
- All Implemented Interfaces:
- Serializable, Node
public class TableScanOperator
- extends Operator<TableScanDesc>
- implements Serializable
Table Scan Operator If the data is coming from the map-reduce framework, just
forward it. This will be needed as part of local work when data is not being
read as part of map-reduce framework
- See Also:
- Serialized Form
Fields inherited from class org.apache.hadoop.hive.ql.exec.Operator |
alias, beginTime, childOperators, childOperatorsArray, childOperatorsTag, colExprMap, conf, counterNames, counterNameToEnum, counters, done, fatalErrorCntr, groupKeyObject, id, inputObjInspectors, inputRows, LOG, numInputRowsCntr, numOutputRowsCntr, operatorId, out, outputObjInspector, outputRows, parentOperators, reporter, state, statsMap, timeTakenCntr, totalTime |
Methods inherited from class org.apache.hadoop.hive.ql.exec.Operator |
allInitializedParentsAreClosed, areAllParentsInitialized, assignCounterNameToEnum, augmentPlan, checkFatalErrors, close, closeOp, dump, dump, endGroup, fatalErrorMessage, forward, getChildOperators, getChildren, getColumnExprMap, getConf, getCounterNames, getCounterNameToEnum, getCounters, getDone, getExecContext, getGroupKeyObject, getIdentifier, getOperatorId, getParentOperators, getSchema, getStats, incrCounter, initEvaluators, initEvaluatorsAndReturnStruct, initialize, initializeChildren, initializeCounters, initializeLocalWork, initializeOp, initOperatorId, jobClose, logStats, passExecContext, preorderMap, process, removeChild, replaceChild, replaceParent, resetId, resetLastEnumUsed, resetStats, setAlias, setChildOperators, setColumnExprMap, setConf, setCounterNames, setCounterNameToEnum, setDone, setExecContext, setGroupKeyObject, setId, setOperatorId, setOutputCollector, setParentOperators, setReporter, setSchema, startGroup, updateCounters |
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
TableScanOperator
public TableScanOperator()
processOp
public void processOp(Object row,
int tag)
throws HiveException
- Currently, the table scan operator does not do anything special other than
just forwarding the row. Since the table data is always read as part of the
map-reduce framework by the mapper. But, this assumption is not true, i.e
table data is not only read by the mapper, this operator will be enhanced
to read the table.
- Specified by:
processOp
in class Operator<TableScanDesc>
- Parameters:
row
- The object representing the row.tag
- The tag of the row usually means which parent this row comes from.
Rows with the same tag should have exactly the same rowInspector
all the time.
- Throws:
HiveException
getName
public String getName()
- The operator name for this operator type. This is used to construct the
rule for an operator
- Specified by:
getName
in interface Node
- Overrides:
getName
in class Operator<TableScanDesc>
- Returns:
- the operator name
setNeededColumnIDs
public void setNeededColumnIDs(ArrayList<Integer> orign_columns)
getNeededColumnIDs
public ArrayList<Integer> getNeededColumnIDs()
getType
public int getType()
- Description copied from class:
Operator
- Should be overridden to return the type of the specific operator among the
types in OperatorType.
- Overrides:
getType
in class Operator<TableScanDesc>
- Returns:
- OperatorType.* or -1 if not overridden
Copyright © 2010 The Apache Software Foundation