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
Field Summary |
protected org.apache.hadoop.mapred.JobConf |
jc
|
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, isLogInfoEnabled, 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, cleanUpInputFileChanged, close, dump, dump, endGroup, fatalErrorMessage, forward, getChildOperators, getChildren, getColumnExprMap, getConf, getCounterNames, getCounterNameToEnum, getCounters, getDone, getExecContext, getGroupKeyObject, getIdentifier, getInputObjInspectors, getOperatorId, getParentOperators, getSchema, getStats, incrCounter, initEvaluators, initEvaluators, initEvaluatorsAndReturnStruct, initialize, initializeChildren, initializeCounters, initializeLocalWork, initOperatorId, jobClose, logStats, passExecContext, preorderMap, process, removeChild, removeChildAndAdoptItsChildren, removeParent, replaceChild, replaceParent, reset, resetId, resetLastEnumUsed, resetStats, setAlias, setChildOperators, setColumnExprMap, setConf, setCounterNames, setCounterNameToEnum, setDone, setExecContext, setGroupKeyObject, setId, setInputObjInspectors, 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 |
jc
protected transient org.apache.hadoop.mapred.JobConf jc
TableScanOperator
public TableScanOperator()
getTableDesc
public TableDesc getTableDesc()
setTableDesc
public void setTableDesc(TableDesc tableDesc)
processOp
public void processOp(Object row,
int tag)
throws HiveException
- Other than gathering statistics for the ANALYZE command, 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, when this
assumption stops to be true, i.e table data won't be 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
cleanUpInputFileChangedOp
public void cleanUpInputFileChangedOp()
throws HiveException
- Overrides:
cleanUpInputFileChangedOp
in class Operator<TableScanDesc>
- Throws:
HiveException
initializeOp
protected void initializeOp(org.apache.hadoop.conf.Configuration hconf)
throws HiveException
- Description copied from class:
Operator
- Operator specific initialization.
- Overrides:
initializeOp
in class Operator<TableScanDesc>
- Throws:
HiveException
closeOp
public void closeOp(boolean abort)
throws HiveException
- Description copied from class:
Operator
- Operator specific close routine. Operators which inherents this class
should overwrite this funtion for their specific cleanup routine.
- Overrides:
closeOp
in class Operator<TableScanDesc>
- 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 OperatorType getType()
- Description copied from class:
Operator
- Return the type of the specific operator among the
types in OperatorType.
- Specified by:
getType
in class Operator<TableScanDesc>
- Returns:
- OperatorType.*
Copyright © 2011 The Apache Software Foundation