org.apache.derby.impl.sql.execute

Class FKInfo

java.lang.Object

org.apache.derby.impl.sql.execute.FKInfo

All Implemented Interfaces:

java.io.Externalizable, java.io.Serializable, Formatable, TypedFormat

public class FKInfo
extends java.lang.Object
implements Formatable

This is a simple class used to store the run time information about a foreign key. Used by DML to figure out what to check.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
int[]	colArray
long[]	fkConglomNumbers
java.lang.String[]	fkConstraintNames
boolean[]	fkIsSelfReferencing
UUID[]	fkUUIDs
static int	FOREIGN_KEY This class implements Formatable.
int[]	raRules
long	refConglomNumber
static int	REFERENCED_KEY
UUID	refUUID
RowLocation	rowLocation
int	stmtType
java.lang.String	tableName
int	type

Constructor Summary

Constructors

Constructor and Description
FKInfo() Niladic constructor for Formattable
FKInfo(java.lang.String[] fkConstraintNames, java.lang.String tableName, int stmtType, int type, UUID refUUID, long refConglomNumber, UUID[] fkUUIDs, long[] fkConglomNumbers, boolean[] fkIsSelfReferencing, int[] colArray, RowLocation rowLocation, int[] raRules) Consructor for FKInfo

Method Summary

Methods

Modifier and Type	Method and Description
static FKInfo[]	chooseRelevantFKInfos(FKInfo[] fkInfo, int[] cols, boolean addAllTypeIsFK) Comb through the FKInfo structures and pick out the ones that have columns that intersect with the input columns.
int	getTypeFormatId() Get the formatID which corresponds to this class.
void	readExternal(java.io.ObjectInput in) Read this object from a stream of stored objects.
java.lang.String	toString()
void	writeExternal(java.io.ObjectOutput out) Write this object out

Methods inherited from class java.lang.Object

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

Field Detail

FOREIGN_KEY

public static final int FOREIGN_KEY

This class implements Formatable. That means that it can write itself to and from a formatted stream. If you add more fields to this class, make sure that you also write/read them with the writeExternal()/readExternal() methods. If, inbetween releases, you add more fields to this class, then you should bump the version number emitted by the getTypeFormatId() method. OR, since this is something that is used in stored prepared statements, it is ok to change it if you make sure that stored prepared statements are invalidated across releases.

See Also:

Constant Field Values

REFERENCED_KEY

public static final int REFERENCED_KEY

See Also:

Constant Field Values

fkConstraintNames

public java.lang.String[] fkConstraintNames

tableName

public java.lang.String tableName

type

public int type

refUUID

public UUID refUUID

refConglomNumber

public long refConglomNumber

fkUUIDs

public UUID[] fkUUIDs

fkConglomNumbers

public long[] fkConglomNumbers

fkIsSelfReferencing

public boolean[] fkIsSelfReferencing

colArray

public int[] colArray

stmtType

public int stmtType

rowLocation

public RowLocation rowLocation

raRules

public int[] raRules

Constructor Detail

FKInfo

public FKInfo()

Niladic constructor for Formattable

FKInfo

public FKInfo(java.lang.String[] fkConstraintNames,
      java.lang.String tableName,
      int stmtType,
      int type,
      UUID refUUID,
      long refConglomNumber,
      UUID[] fkUUIDs,
      long[] fkConglomNumbers,
      boolean[] fkIsSelfReferencing,
      int[] colArray,
      RowLocation rowLocation,
      int[] raRules)

Consructor for FKInfo

Parameters:

fkConstraintNames - the foreign key constraint names

tableName - the name of the table being modified

stmtType - the type of the statement: e.g. StatementType.INSERT

type - either FKInfo.REFERENCED_KEY or FKInfo.FOREIGN_KEY

refUUID - UUID of the referenced constraint

refConglomNumber - congomerate number of the referenced key

fkUUIDs - an array of fkUUIDs of backing indexes. if FOREIGN_KEY, then just one element, the backing index of the referrenced keys. if REFERENCED_KEY, then all the foreign keys

fkConglomNumbers - array of conglomerate numbers, corresponds to fkUUIDs

fkIsSelfReferencing - array of conglomerate booleans indicating whether the fk references a key in the same table

colArray - map of columns to the base row that DML is changing. 1 based. Note that this maps the constraint index to a row in the target table of the current dml operation.

rowLocation - a row location template for the target table used to pass in a template row to tc.openScan()

Method Detail

chooseRelevantFKInfos

public static FKInfo[] chooseRelevantFKInfos(FKInfo[] fkInfo,
                             int[] cols,
                             boolean addAllTypeIsFK)

Comb through the FKInfo structures and pick out the ones that have columns that intersect with the input columns.

Parameters:

fkInfo - array of fkinfos

cols - array of columns

addAllTypeIsFK - take all with type == FORIEGN_KEY

Returns:

array of relevant fkinfos

writeExternal

public void writeExternal(java.io.ObjectOutput out)
                   throws java.io.IOException

Write this object out

Specified by:

writeExternal in interface java.io.Externalizable

Parameters:

out - write bytes here

Throws:

java.io.IOException - thrown on error

readExternal

public void readExternal(java.io.ObjectInput in)
                  throws java.io.IOException,
                         java.lang.ClassNotFoundException

Read this object from a stream of stored objects.

Specified by:

readExternal in interface java.io.Externalizable

Parameters:

in - read this.

Throws:

java.io.IOException - thrown on error

java.lang.ClassNotFoundException - thrown on error

getTypeFormatId

public int getTypeFormatId()

Get the formatID which corresponds to this class.

Specified by:

getTypeFormatId in interface TypedFormat

Returns:

the formatID of this class

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object