org.axiondb.engine.tables
Class ExternalDatabaseTable

java.lang.Object
  org.axiondb.event.BaseTableModificationPublisher
      org.axiondb.engine.tables.BaseTable
          org.axiondb.engine.tables.ExternalDatabaseTable

All Implemented Interfaces:

ExternalTable, RowSource, Table, Transactable, TransactableTable

public class ExternalDatabaseTable

extends BaseTable

implements ExternalTable, TransactableTable

Base implementation of ExternalTable interface.

Example: create external table emp (lname varchar(80), sid integer(6), fname varchar(80), id integer(6) not null, dob timestamp(6)) organization (loadtype='remote' SERVER='myserver' REMOTETABLE='mytablename' SCHEMA='myschema' ORDERBY='id' WHERE='id > 1000');

Note : We have tested this for Oracle 8i/9i , SQL Server, Sybase.
If you use WHERE, ORDER BY it is almost similar to creating a remote view, and you will not be able to update it. We use Scrollable ResultSet to perform Insert/Update/Delete operations, which may have some perfermance concern depending on the data size.

TODO: Use prepare statement for update and insert

TODO: Use Vendor specific code for truncate, table exists check, escape id

TODO: Support remote table drop, create/drop index, create/drop constraint

DROP DATABASE LINK should de-link the table and drop table should drop table on remote as well as local

Version:

$Revision: 1.2 $ $Date: 2004/09/09 23:47:44 $

See Also:

DatabaseLink

Field Summary

static String	PROP_CATALOG Property key name for catalog name
static String	PROP_DB Property key name for database link
static String	PROP_ORDERBY Property key name for where filter
static String	PROP_REMOTETABLE Property key name for remote table name
static String	PROP_SCHEMA Property key name for schema name
static String	PROP_WHERE Property key name for where filter

Fields inherited from interface org.axiondb.ExternalTable

DELIMITED_TABLE_TYPE, EXTERNAL_DB_TABLE_TYPE, FW_TABLE_TYPE, PROP_LOADTYPE, TAGGED_EBCDIC_TABLE_TYPE

Fields inherited from interface org.axiondb.Table

REGULAR_TABLE_TYPE, SYSTEM_TABLE_TYPE

Constructor Summary

ExternalDatabaseTable(String name, Database db)

Method Summary

void	addConstraint(Constraint constraint)
void	apply() Apply this committedtransaction..
void	applyDeletes(org.apache.commons.collections.primitives.IntCollection rowIds) Remove the specified rows from this table and any associated indices.
void	applyInserts(Collection rows) Insert the given rows into this table and any associated indices.
void	applyUpdates(Collection rows) Update the given rows in this table and any associated indices.
protected void	assertConnection()
protected void	assertExternalResultSet()
protected void	assertUpdatable()
protected void	checkConstraints(RowEvent event)
void	commit() This transaction has been committed.
protected void	createOrLoadResultSet(boolean unconditionally)
protected void	createRemoteTableIfNotExists()
protected void	createResultSet()
void	drop() Drop this table from the database.
void	freeRowId(int id) Un-reserve a row id.
protected String	getCreateSQL()
protected String	getInsertSQL()
int	getNextRowId() Reserve a row id.
Row	getRow(int id)
protected Row	getRowByOffset(int rowId)
int	getRowCount() Return the number of Rows I contain.
protected RowIterator	getRowIterator()
protected String	getSelectSQL(String where, List orderByColumns)
Properties	getTableProperties() Gets Organization Property.
TransactableTable	makeTransactableTable() Create a TransactableTablefor this table.
void	populateIndex(Index index) Populate an Index, adding my current rows to it.
void	remount()
void	removeConstraint(String name)
void	rollback() This transaction has been aborted.
boolean	setTableProperties(Properties props) Sets collection of configuration properties for this external table to the given Properties instance.
protected void	setUp(DatabaseLink server)
void	shutdown() The database is shutting down, shutdown this table also.
protected boolean	tableExistsInRemoteDB()
void	truncate() Unconditionally delete all rows in this table.

Methods inherited from class org.axiondb.engine.tables.BaseTable

addColumn, addIndex, addRow, applyDeletesToIndices, applyInsertsToIndices, applyUpdatesToIndices, checkConstraints, deleteRow, getColumn, getColumn, getColumnCount, getColumnIdentifiers, getColumnIndex, getConstraints, getIndexedRows, getIndexForColumn, getIndices, getMatchingRows, getName, getRowIterator, getType, hasColumn, hasDeferredConstraint, hasIndex, isColumnIndexed, isPrimaryKeyConstraintExists, isUniqueConstraintExists, makeRowDecorator, notifyColumnsOfNewLobDir, readColumns, readConstraints, remount, removeIndex, rename, setName, setType, toString, truncateIndices, updateRow, writeColumns, writeConstraints

Methods inherited from class org.axiondb.event.BaseTableModificationPublisher

addTableModificationListener, getTableModificationListeners, publishEvent, removeTableModificationListener

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.axiondb.Table

addColumn, addIndex, addRow, addTableModificationListener, getColumn, getColumn, getColumnCount, getColumnIdentifiers, getColumnIndex, getConstraints, getIndexedRows, getIndexForColumn, getIndices, getMatchingRows, getName, getRowIterator, getType, hasColumn, hasIndex, isColumnIndexed, isPrimaryKeyConstraintExists, isUniqueConstraintExists, makeRowDecorator, remount, removeIndex, removeTableModificationListener, rename, updateRow

Field Detail

PROP_CATALOG

public static final String PROP_CATALOG

Property key name for catalog name

See Also:

Constant Field Values

PROP_DB

public static final String PROP_DB

Property key name for database link

See Also:

Constant Field Values

PROP_ORDERBY

public static final String PROP_ORDERBY

Property key name for where filter

See Also:

Constant Field Values

PROP_REMOTETABLE

public static final String PROP_REMOTETABLE

Property key name for remote table name

See Also:

Constant Field Values

PROP_SCHEMA

public static final String PROP_SCHEMA

Property key name for schema name

See Also:

Constant Field Values

PROP_WHERE

public static final String PROP_WHERE

Property key name for where filter

See Also:

Constant Field Values

Constructor Detail

ExternalDatabaseTable

public ExternalDatabaseTable(String name,
                             Database db)

Method Detail

addConstraint

public void addConstraint(Constraint constraint)
                   throws AxionException

Specified by:

addConstraint in interface Table

Overrides:

addConstraint in class BaseTable

Throws:

AxionException

removeConstraint

public void removeConstraint(String name)

Specified by:

removeConstraint in interface Table

Overrides:

removeConstraint in class BaseTable

applyDeletes

public void applyDeletes(org.apache.commons.collections.primitives.IntCollection rowIds)
                  throws AxionException

Description copied from interface: Table

Remove the specified rows from this table and any associated indices. This process is allowed to be destructive, the table my delete values from the given list.

Specified by:

applyDeletes in interface Table

Specified by:

applyDeletes in class BaseTable

Throws:

AxionException

applyInserts

public void applyInserts(Collection rows)
                  throws AxionException

Description copied from interface: Table

Insert the given rows into this table and any associated indices. This process is allowed to be destructive, the table my delete rows from the given list.

Specified by:

applyInserts in interface Table

Specified by:

applyInserts in class BaseTable

Throws:

AxionException

applyUpdates

public void applyUpdates(Collection rows)
                  throws AxionException

Description copied from interface: Table

Update the given rows in this table and any associated indices. This process is allowed to be destructive, the table my delete rows from the given list.

Specified by:

applyUpdates in interface Table

Specified by:

applyUpdates in class BaseTable

Throws:

AxionException

remount

public void remount()
             throws AxionException

Specified by:

remount in interface ExternalTable

Throws:

AxionException

drop

public void drop()
          throws AxionException

Description copied from interface: Table

Drop this table from the database.

Specified by:

drop in interface Table

Overrides:

drop in class BaseTable

Throws:

AxionException

freeRowId

public void freeRowId(int id)

Description copied from interface: Table

Un-reserve a row id.

Specified by:

freeRowId in interface Table

Specified by:

freeRowId in class BaseTable

getNextRowId

public int getNextRowId()

Description copied from interface: Table

Reserve a row id.

Specified by:

getNextRowId in interface Table

Specified by:

getNextRowId in class BaseTable

getRow

public Row getRow(int id)
           throws AxionException

Specified by:

getRow in interface RowSource

Specified by:

getRow in class BaseTable

Throws:

AxionException

getRowCount

public int getRowCount()

Description copied from interface: Table

Return the number of Rows I contain.

Specified by:

getRowCount in interface Table

Specified by:

getRowCount in class BaseTable

populateIndex

public void populateIndex(Index index)
                   throws AxionException

Description copied from interface: Table

Populate an Index, adding my current rows to it. Does not addthe index.

Specified by:

populateIndex in interface Table

Specified by:

populateIndex in class BaseTable

Throws:

AxionException

setTableProperties

public boolean setTableProperties(Properties props)
                           throws AxionException

Description copied from interface: ExternalTable

Sets collection of configuration properties for this external table to the given Properties instance. This describe how the data is stored the existing data file.

Specified by:

setTableProperties in interface ExternalTable

Parameters:

props - configuration properties for this external table

Throws:

AxionException

getTableProperties

public Properties getTableProperties()

Description copied from interface: ExternalTable

Gets Organization Property.

Specified by:

getTableProperties in interface ExternalTable

Returns:

Set of organization property key names;

shutdown

public void shutdown()
              throws AxionException

Description copied from interface: Table

The database is shutting down, shutdown this table also.

Specified by:

shutdown in interface Table

Overrides:

shutdown in class BaseTable

Throws:

AxionException

truncate

public void truncate()
              throws AxionException

Description copied from interface: Table

Unconditionally delete all rows in this table.

Specified by:

truncate in interface Table

Returns:

true if truncation succeeded; false otherwise

Throws:

AxionException

apply

public void apply()
           throws AxionException

Description copied from interface: Transactable

Apply this committedtransaction..

Specified by:

apply in interface Transactable

Throws:

AxionException

commit

public void commit()
            throws AxionException

Description copied from interface: Transactable

This transaction has been committed.

Specified by:

commit in interface Transactable

Throws:

AxionException

rollback

public void rollback()
              throws AxionException

Description copied from interface: Transactable

This transaction has been aborted.

Specified by:

rollback in interface Transactable

Throws:

AxionException

makeTransactableTable

public TransactableTable makeTransactableTable()

Description copied from interface: Table

Create a TransactableTablefor this table.

Specified by:

makeTransactableTable in interface Table

Overrides:

makeTransactableTable in class BaseTable

assertConnection

protected void assertConnection()
                         throws AxionException

Throws:

AxionException

assertExternalResultSet

protected void assertExternalResultSet()
                                throws AxionException

Throws:

AxionException

assertUpdatable

protected void assertUpdatable()
                        throws AxionException

Throws:

AxionException

checkConstraints

protected void checkConstraints(RowEvent event)
                         throws AxionException

Overrides:

checkConstraints in class BaseTable

Throws:

AxionException

createOrLoadResultSet

protected void createOrLoadResultSet(boolean unconditionally)
                              throws AxionException

Throws:

AxionException

createRemoteTableIfNotExists

protected void createRemoteTableIfNotExists()
                                     throws AxionException

Throws:

AxionException

createResultSet

protected void createResultSet()
                        throws AxionException

Throws:

AxionException

getCreateSQL

protected String getCreateSQL()

getRowByOffset

protected Row getRowByOffset(int rowId)
                      throws AxionException

Throws:

AxionException

getRowIterator

protected RowIterator getRowIterator()
                              throws AxionException

Specified by:

getRowIterator in class BaseTable

Throws:

AxionException

getSelectSQL

protected String getSelectSQL(String where,
                              List orderByColumns)

setUp

protected void setUp(DatabaseLink server)
              throws AxionException

Throws:

AxionException

tableExistsInRemoteDB

protected boolean tableExistsInRemoteDB()
                                 throws AxionException

Throws:

AxionException

getInsertSQL

protected String getInsertSQL()