FKInfo (Apache Derby V10.14 Internals)

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	Description
`(package private) int[]`	`colArray`
`(package private) boolean[]`	`deferrable`
`(package private) long[]`	`fkConglomNumbers`
`(package private) java.lang.String[]`	`fkConstraintNames`
`(package private) UUID[]`	`fkIds`
`(package private) boolean[]`	`fkIsSelfReferencing`
`private UUID[]`	`fkUUIDs`
`static int`	`FOREIGN_KEY`	This class implements Formatable.
`(package private) int[]`	`raRules`
`(package private) long`	`refConglomNumber`
`(package private) UUID`	`refConstraintID`
`(package private) boolean`	`refConstraintIsDeferrable`
`static int`	`REFERENCED_KEY`
`(package private) UUID`	`refUUID`
`(package private) RowLocation`	`rowLocation`
`(package private) java.lang.String`	`schemaName`
`(package private) int`	`stmtType`
`(package private) java.lang.String`	`tableName`
`(package private) int`	`type`

Constructor Summary

Constructors
Constructor	Description
`FKInfo()`	Niladic constructor for Formattable
`FKInfo(java.lang.String[] fkConstraintNames, java.lang.String schemaName, java.lang.String tableName, int stmtType, int type, UUID refUUID, long refConglomNumber, UUID refConstraintID, boolean refConstraintIsDeferrable, UUID[] fkUUIDs, long[] fkConglomNumbers, boolean[] fkIsSelfReferencing, int[] colArray, RowLocation rowLocation, int[] raRules, boolean[] deferrable, UUID[] fkIds)`	Constructor for FKInfo

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	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, between 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
  - schemaName
```
java.lang.String schemaName
```
  - tableName
```
java.lang.String tableName
```
  - type
```
int type
```
  - refUUID
```
UUID refUUID
```
  - refConglomNumber
```
long refConglomNumber
```
  - refConstraintID
```
UUID refConstraintID
```
  - refConstraintIsDeferrable
```
boolean refConstraintIsDeferrable
```
  - stmtType
```
int stmtType
```
  - rowLocation
```
RowLocation rowLocation
```
  - fkConstraintNames
```
java.lang.String[] fkConstraintNames
```
  - fkUUIDs
```
private UUID[] fkUUIDs
```
  - fkConglomNumbers
```
long[] fkConglomNumbers
```
  - fkIds
```
UUID[] fkIds
```
  - fkIsSelfReferencing
```
boolean[] fkIsSelfReferencing
```
  - colArray
```
int[] colArray
```
  - raRules
```
int[] raRules
```
  - deferrable
```
boolean[] deferrable
```
- Constructor Detail
  - FKInfo
```
public FKInfo()
```
    Niladic constructor for Formattable
  - FKInfo
```
public FKInfo(java.lang.String[] fkConstraintNames,
              java.lang.String schemaName,
              java.lang.String tableName,
              int stmtType,
              int type,
              UUID refUUID,
              long refConglomNumber,
              UUID refConstraintID,
              boolean refConstraintIsDeferrable,
              UUID[] fkUUIDs,
              long[] fkConglomNumbers,
              boolean[] fkIsSelfReferencing,
              int[] colArray,
              RowLocation rowLocation,
              int[] raRules,
              boolean[] deferrable,
              UUID[] fkIds)
```
    Constructor for FKInfo
    
    Parameters:
    
    fkConstraintNames - the foreign key constraint names
    
    schemaName - the name of the schema of the table being modified
    
    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's supporting index
    
    refConglomNumber - conglomerate number of the referenced key
    
    refConstraintID - UUID of the referenced constraint
    
    refConstraintIsDeferrable - true iff the referenced key constraint is deferrable
    
    fkUUIDs - an array of fkUUIDs of backing indexes. if FOREIGN_KEY, then just one element, the backing index of the referenced 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 foreign key 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()
    
    raRules - referential action rules
    
    deferrable - the corresponding constraint is deferrable
    
    fkIds - the foreign key constraints' uuids.
- 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 == FOREIGN_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

Class FKInfo

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

FOREIGN_KEY

REFERENCED_KEY

schemaName

tableName

type

refUUID

refConglomNumber

refConstraintID

refConstraintIsDeferrable

stmtType

rowLocation

fkConstraintNames

fkUUIDs

fkConglomNumbers

fkIds

fkIsSelfReferencing

colArray

raRules

deferrable

Constructor Detail

FKInfo

FKInfo

Method Detail

chooseRelevantFKInfos

writeExternal

readExternal

getTypeFormatId

toString