org.apache.derby.impl.sql.execute
Class GenericRIChecker

java.lang.Object
  org.apache.derby.impl.sql.execute.GenericRIChecker

Direct Known Subclasses:

ForeignKeyRIChecker, ReferencedKeyRIChecker

public abstract class GenericRIChecker
extends java.lang.Object

Generic implementation of a Referential Integrity checker. Abstract.

Field Summary

protected DynamicCompiledOpenConglomInfo[]	fkDcocis
protected FKInfo	fkInfo
protected StaticCompiledOpenConglomInfo[]	fkScocis
private IndexRow	indexQualifierRow
private int	numColumns
protected DynamicCompiledOpenConglomInfo	refDcoci
protected StaticCompiledOpenConglomInfo	refScoci
private java.util.Hashtable	scanControllers
protected TransactionController	tc

Constructor Summary

GenericRIChecker(TransactionController tc, FKInfo fkinfo)

Method Summary

(package private) void	close() Clean up all scan controllers
void	doCheck(ExecRow row)
(package private) abstract void	doCheck(ExecRow row, boolean restrictCheckOnly) Check the validity of this row
(package private) int	getRICheckIsolationLevel() Get the isolation level for the scan for the RI check.
protected ScanController	getScanController(long conglomNumber, StaticCompiledOpenConglomInfo scoci, DynamicCompiledOpenConglomInfo dcoci, ExecRow searchRow) Get a scan controller positioned using searchRow as the start/stop position.
(package private) boolean	isAnyFieldNull(ExecRow baseRow) Are any of the fields null in the row passed in.
private void	setupQualifierRow(ExecRow baseRow)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

fkInfo

protected FKInfo fkInfo

fkDcocis

protected DynamicCompiledOpenConglomInfo[] fkDcocis

fkScocis

protected StaticCompiledOpenConglomInfo[] fkScocis

refDcoci

protected DynamicCompiledOpenConglomInfo refDcoci

refScoci

protected StaticCompiledOpenConglomInfo refScoci

tc

protected TransactionController tc

scanControllers

private java.util.Hashtable scanControllers

numColumns

private int numColumns

indexQualifierRow

private IndexRow indexQualifierRow

Constructor Detail

GenericRIChecker

GenericRIChecker(TransactionController tc,
                 FKInfo fkinfo)
           throws StandardException

Parameters:

tc - the xact controller

fkinfo - the foreign key information

Throws:

StandardException - Thrown on failure

Method Detail

doCheck

abstract void doCheck(ExecRow row,
                      boolean restrictCheckOnly)
               throws StandardException

Check the validity of this row

Parameters:

row - the row to check

Throws:

StandardException - on error

doCheck

public void doCheck(ExecRow row)
             throws StandardException

Throws:

StandardException

getScanController

protected ScanController getScanController(long conglomNumber,
                                           StaticCompiledOpenConglomInfo scoci,
                                           DynamicCompiledOpenConglomInfo dcoci,
                                           ExecRow searchRow)
                                    throws StandardException

Get a scan controller positioned using searchRow as the start/stop position. The assumption is that searchRow is of the same format as the index being opened. The scan is set up to return no columns. NOTE: We only need an instantaneous lock on the table that we are probing as we are just checking for the existance of a row. All updaters, whether to the primary or foreign key tables, will hold an X lock on the table that they are updating and will be probing the other table, so instantaneous locks will not change the semantics. RESOLVE: Due to the current RI implementation we cannot always get instantaneous locks. We will call a method to find out what kind of locking to do until the implementation changes.

Parameters:

conglomNumber - the particular conglomerate we are interested in

searchRow - the row to match

Throws:

StandardException - on error

setupQualifierRow

private void setupQualifierRow(ExecRow baseRow)

isAnyFieldNull

boolean isAnyFieldNull(ExecRow baseRow)

Are any of the fields null in the row passed in. The only fields that are checked are those corresponding to the colArray in fkInfo.

close

void close()
     throws StandardException

Clean up all scan controllers

Throws:

StandardException - on error

getRICheckIsolationLevel

int getRICheckIsolationLevel()

Get the isolation level for the scan for the RI check. NOTE: The level will eventually be instantaneous locking once the implemenation changes.

Returns:

The isolation level for the scan for the RI check.