org.apache.derby.iapi.sql.dictionary
Class ReferencedKeyConstraintDescriptor

java.lang.Object
  org.apache.derby.iapi.sql.dictionary.TupleDescriptor
      org.apache.derby.iapi.sql.dictionary.ConstraintDescriptor
          org.apache.derby.iapi.sql.dictionary.KeyConstraintDescriptor
              org.apache.derby.iapi.sql.dictionary.ReferencedKeyConstraintDescriptor

All Implemented Interfaces:

Dependable, Dependent, Provider, UniqueTupleDescriptor

public class ReferencedKeyConstraintDescriptor
extends KeyConstraintDescriptor

A ReferencedConstraintDeescriptor is a primary key or a unique key that is referenced by a foreign key.

Field Summary

private boolean	checkedSelfReferencing
private int	constraintType public interface to this descriptor: public boolean hasSelfReferencingFK(ConstraintDescriptorList cdl, int type) throws StandardException; public ConstraintDescriptorList getForeignKeyConstraints(int type) throws StandardException; public boolean isReferenced(); public int getReferenceCount(); public int incrementReferenceCount(); public int decrementReferenceCount();
private ConstraintDescriptorList	fkConstraintList
private ConstraintDescriptorList	fkEnabledConstraintList
private boolean	hasSelfReferencing
(package private) int	referenceCount

Fields inherited from class org.apache.derby.iapi.sql.dictionary.KeyConstraintDescriptor

indexId

Fields inherited from class org.apache.derby.iapi.sql.dictionary.ConstraintDescriptor

ALL, constraintId, constraintName, DISABLED, ENABLED, isEnabled, SYSCONSTRAINTS_STATE_FIELD, table

Fields inherited from interface org.apache.derby.catalog.Dependable

ACTIVATION, ALIAS, COLUMNS_IN_TABLE, COLUMNS_PERMISSION, CONGLOMERATE, CONSTRAINT, DEFAULT, FILE, HEAP, INDEX, PERM, PREPARED_STATEMENT, ROLE_GRANT, ROUTINE_PERMISSION, SCHEMA, SEQUENCE, STORED_PREPARED_STATEMENT, TABLE, TABLE_PERMISSION, TRIGGER, VIEW

Constructor Summary

protected

ReferencedKeyConstraintDescriptor(int constraintType, DataDictionary dataDictionary, TableDescriptor table, java.lang.String constraintName, boolean deferrable, boolean initiallyDeferred, int[] columns, UUID constraintId, UUID indexId, SchemaDescriptor schemaDesc, boolean isEnabled, int referenceCount) Constructor for a KeyConstraintDescriptorImpl

Method Summary

private void	checkType(int type)
int	decrementReferenceCount() Decrement the reference count by one.
int	getConstraintType() Gets an identifier telling what type of descriptor it is (UNIQUE, PRIMARY KEY, FOREIGN KEY, CHECK).
ConstraintDescriptorList	getForeignKeyConstraints(int type) Get the referencing foreign key constraints
int	getReferenceCount() Get the number of enabled fks that reference this key.
boolean	hasNonSelfReferencingFK(int type) Am I referenced by a FK on another table?
boolean	hasSelfReferencingFK(ConstraintDescriptorList cdl, int type) Am I referenced by a FK on the same table?
int	incrementReferenceCount() Bump the reference count by one.
boolean	isReferenced() Is this constraint referenced?
boolean	needsToFire(int stmtType, int[] modifiedCols) Does this constraint need to fire on this type of DML?

Methods inherited from class org.apache.derby.iapi.sql.dictionary.KeyConstraintDescriptor

getConglomerateId, getIndexConglomerateDescriptor, getIndexId, getIndexUUIDString, hasBackingIndex, toString

Methods inherited from class org.apache.derby.iapi.sql.dictionary.ConstraintDescriptor

areColumnsComparable, columnIntersects, deferrable, doColumnsIntersect, drop, getClassType, getColumnDescriptors, getConstraintName, getConstraintText, getDependableFinder, getDescriptorName, getDescriptorType, getKeyColumns, getObjectID, getObjectName, getReferencedColumns, getSchemaDescriptor, getTableDescriptor, getTableId, getUUID, initiallyDeferred, isEnabled, isValid, makeInvalid, prepareToInvalidate, setDisabled, setEnabled

Methods inherited from class org.apache.derby.iapi.sql.dictionary.TupleDescriptor

getColumnDependableFinder, getDataDictionary, getDependableFinder, isPersistent, setDataDictionary

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.derby.catalog.Dependable

isPersistent

Field Detail

constraintType

private final int constraintType

public interface to this descriptor:

1. public boolean hasSelfReferencingFK(ConstraintDescriptorList cdl, int type) throws StandardException;
2. public ConstraintDescriptorList getForeignKeyConstraints(int type) throws StandardException;
3. public boolean isReferenced();
4. public int getReferenceCount();
5. public int incrementReferenceCount();
6. public int decrementReferenceCount();

referenceCount

int referenceCount

fkEnabledConstraintList

private ConstraintDescriptorList fkEnabledConstraintList

fkConstraintList

private ConstraintDescriptorList fkConstraintList

checkedSelfReferencing

private boolean checkedSelfReferencing

hasSelfReferencing

private boolean hasSelfReferencing

Constructor Detail

ReferencedKeyConstraintDescriptor

protected ReferencedKeyConstraintDescriptor(int constraintType,
                                            DataDictionary dataDictionary,
                                            TableDescriptor table,
                                            java.lang.String constraintName,
                                            boolean deferrable,
                                            boolean initiallyDeferred,
                                            int[] columns,
                                            UUID constraintId,
                                            UUID indexId,
                                            SchemaDescriptor schemaDesc,
                                            boolean isEnabled,
                                            int referenceCount)

Constructor for a KeyConstraintDescriptorImpl

Parameters:

constraintType - The type of the constraint

dataDictionary - The data dictionary that this descriptor lives in

table - The descriptor of the table the constraint is on

constraintName - The name of the constraint.

deferrable - If the constraint can be deferred.

initiallyDeferred - If the constraint starts life deferred.

columns - columns involved in the constraint

constraintId - UUID of constraint

indexId - The UUID for the backing index

schemaDesc - The SchemaDescriptor for the constraint

isEnabled - is the constraint enabled?

referenceCount - number of FKs (enabled only)

Method Detail

getConstraintType

public final int getConstraintType()

Description copied from class: ConstraintDescriptor

Gets an identifier telling what type of descriptor it is (UNIQUE, PRIMARY KEY, FOREIGN KEY, CHECK).

Specified by:

getConstraintType in class ConstraintDescriptor

Returns:

An identifier telling what type of descriptor it is (UNIQUE, PRIMARY KEY, FOREIGN KEY, CHECK).

hasSelfReferencingFK

public boolean hasSelfReferencingFK(ConstraintDescriptorList cdl,
                                    int type)
                             throws StandardException

Am I referenced by a FK on the same table?

Parameters:

cdl - ConstraintDescriptorList for the table

type - ConstraintDescriptor.(ENABLED|DISABLED|ALL)

Returns:

true/false

Throws:

StandardException - on error

hasNonSelfReferencingFK

public boolean hasNonSelfReferencingFK(int type)
                                throws StandardException

Am I referenced by a FK on another table?

Parameters:

type - ConstraintDescriptor.(ENABLED|DISABLED|ALL)

Returns:

true/false

Throws:

StandardException - on error

getForeignKeyConstraints

public ConstraintDescriptorList getForeignKeyConstraints(int type)
                                                  throws StandardException

Get the referencing foreign key constraints

Parameters:

type - ConstraintDescriptor.(ENABLED|DISABLED|ALL)

Returns:

the list of constraints (ConstraintDescriptorListImpl)

Throws:

StandardException - on error

isReferenced

public boolean isReferenced()

Is this constraint referenced? Returns true if there are enabled fks that reference this constraint.

Overrides:

isReferenced in class ConstraintDescriptor

Returns:

false

getReferenceCount

public int getReferenceCount()

Get the number of enabled fks that reference this key.

Overrides:

getReferenceCount in class ConstraintDescriptor

Returns:

the number of fks

incrementReferenceCount

public int incrementReferenceCount()

Bump the reference count by one.

Returns:

the number of fks

decrementReferenceCount

public int decrementReferenceCount()

Decrement the reference count by one.

Returns:

the number of fks

needsToFire

public boolean needsToFire(int stmtType,
                           int[] modifiedCols)

Does this constraint need to fire on this type of DML? For referenced keys, fire if referenced by a fk, and stmt is delete or bulk insert replace, or stmt is update and columns intersect.

Specified by:

needsToFire in class ConstraintDescriptor

Parameters:

stmtType - the type of DML (StatementType.INSERT|StatementType.UPDATE|StatementType.DELETE)

modifiedCols - the columns modified, or null for all

Returns:

true/false

checkType

private void checkType(int type)
                throws StandardException

Throws:

StandardException