Apache Derby Database Engine and Embedded JDBC Driver 10.17.1.0 · org.apache.derby.impl.sql.execute.IndexColumnOrder

Modifier and Type	Field and Description
pack-priv boolean	ascending
pack-priv int	colNum This class implements Formatable.
pack-priv boolean	nullsOrderedLow indicate whether NULL values should sort low.

Constructor Summary

Access	Constructor and Description
public	IndexColumnOrder() Niladic constructor for formatable
public	IndexColumnOrder(int colNum)
public	IndexColumnOrder(int colNum, boolean ascending)
public	IndexColumnOrder(int number of this column colNum, boolean whether the ORDER BY is ascendeing or descending ascending, boolean whether nulls should be ordered low nullsLow) constructor used by the ORDER BY clause.

Method Summary

Modifier and Type	Method and Description
public int	getColumnId() Implements org.apache.derby.iapi.store.access.ColumnOrdering.getColumnId.
public boolean	getIsAscending() Implements org.apache.derby.iapi.store.access.ColumnOrdering.getIsAscending.
public boolean	Returns: whether nulls should sort low getIsNullsOrderedLow() Implements org.apache.derby.iapi.store.access.ColumnOrdering.getIsNullsOrderedLow. Indicate whether NULL values should be ordered below non-NULL.
public int	Returns: the formatID of this class getTypeFormatId() Implements org.apache.derby.iapi.services.io.TypedFormat.getTypeFormatId. Get the formatID which corresponds to this class.
public void	readExternal(ObjectInput read this. in) Implements java.io.Externalizable.readExternal. Read this object from a stream of stored objects.
public String	toString() Overrides java.lang.Object.toString. Returns a string representation of the object.
public void	writeExternal(ObjectOutput write bytes here out) Implements java.io.Externalizable.writeExternal. Write this object out

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll wait wait wait

Field Detail

ascending	back to summary
pack-priv boolean ascending

colNum	back to summary
pack-priv int colNum 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.

nullsOrderedLow	back to summary
pack-priv boolean nullsOrderedLow indicate whether NULL values should sort low. nullsOrderedLow is usually false, because generally Derby defaults to have NULL values compare higher than non-null values, but if the user specifies an ORDER BY clause with a specification that indicates that NULL values should be ordered lower than non-NULL values, thien nullsOrderedLow is set to true.

Constructor Detail

IndexColumnOrder	back to summary
public IndexColumnOrder() Niladic constructor for formatable

IndexColumnOrder	back to summary
public IndexColumnOrder(int colNum)

IndexColumnOrder	back to summary
public IndexColumnOrder(int colNum, boolean ascending)

IndexColumnOrder	back to summary
public IndexColumnOrder(int colNum, boolean ascending, boolean nullsLow) constructor used by the ORDER BY clause. This version of the constructor is used by the compiler when it processes an ORDER BY clause in a SQL statement. For such statements, the user gets to control whether NULL values are ordered as lower than all non-NULL values, or higher than all non-NULL values. Parameters colNum:int number of this column ascending:boolean whether the ORDER BY is ascendeing or descending nullsLow:boolean whether nulls should be ordered low

IndexColumnOrder

back to summary

public IndexColumnOrder(int colNum, boolean ascending, boolean nullsLow)

constructor used by the ORDER BY clause. This version of the constructor is used by the compiler when it processes an ORDER BY clause in a SQL statement. For such statements, the user gets to control whether NULL values are ordered as lower than all non-NULL values, or higher than all non-NULL values.

Parameters

colNum:int: number of this column
ascending:boolean: whether the ORDER BY is ascendeing or descending
nullsLow:boolean: whether nulls should be ordered low

Method Detail

getColumnId	back to summary
public int getColumnId() Implements org.apache.derby.iapi.store.access.ColumnOrdering.getColumnId.

getIsAscending	back to summary
public boolean getIsAscending() Implements org.apache.derby.iapi.store.access.ColumnOrdering.getIsAscending.

getIsNullsOrderedLow	back to summary
public boolean getIsNullsOrderedLow() Implements org.apache.derby.iapi.store.access.ColumnOrdering.getIsNullsOrderedLow. Indicate whether NULL values should be ordered below non-NULL. This function returns TRUE if the user has specified, via the clause in the ORDER BY clause, that NULL values of this column should sort lower than non-NULL values. Returns:boolean whether nulls should sort low

getIsNullsOrderedLow

back to summary

public boolean getIsNullsOrderedLow()

Implements org.apache.derby.iapi.store.access.ColumnOrdering.getIsNullsOrderedLow.

Indicate whether NULL values should be ordered below non-NULL. This function returns TRUE if the user has specified, via the clause in the ORDER BY clause, that NULL values of this column should sort lower than non-NULL values.

Returns:boolean: whether nulls should sort low

getTypeFormatId	back to summary
public int getTypeFormatId() Implements org.apache.derby.iapi.services.io.TypedFormat.getTypeFormatId. Get the formatID which corresponds to this class. Returns:int the formatID of this class

getTypeFormatId

back to summary

public int getTypeFormatId()

Implements org.apache.derby.iapi.services.io.TypedFormat.getTypeFormatId.

Get the formatID which corresponds to this class.

Returns:int: the formatID of this class

readExternal	back to summary
public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException Implements java.io.Externalizable.readExternal. Read this object from a stream of stored objects. Parameters in:ObjectInput read this. Exceptions IOException: thrown on error ClassNotFoundException: thrown on error

readExternal

back to summary

public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException

Implements java.io.Externalizable.readExternal.

Read this object from a stream of stored objects.

Parameters

in:ObjectInput: read this.

Exceptions

IOException:: thrown on error
ClassNotFoundException:: thrown on error

toString back to summary

toString	back to summary
public String toString() Overrides java.lang.Object.toString. Doc from java.lang.Object.toString. Returns a string representation of the object. Satisfying this method's contract implies a non-`null` result must be returned. Returns:String a string representation of the object

public String toString()

Overrides java.lang.Object.toString.

Doc from java.lang.Object.toString.

Returns a string representation of the object. Satisfying this method's contract implies a non-null result must be returned.

Returns:String: a string representation of the object

writeExternal	back to summary
public void writeExternal(ObjectOutput out) throws IOException Implements java.io.Externalizable.writeExternal. Write this object out Parameters out:ObjectOutput write bytes here Exceptions IOException: thrown on error

writeExternal

back to summary

public void writeExternal(ObjectOutput out) throws IOException

Implements java.io.Externalizable.writeExternal.

Write this object out

Parameters

out:ObjectOutput: write bytes here

Exceptions

IOException:: thrown on error

public Class IndexColumnOrder

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail