org.mmbase.storage.database
Class RelationalDatabaseStorage

java.lang.Object
  |
  +--org.mmbase.storage.database.Support2Storage
        |
        +--org.mmbase.storage.database.AbstractDatabaseStorage
              |
              +--org.mmbase.storage.database.SQL92DatabaseStorage
                    |
                    +--org.mmbase.storage.database.RelationalDatabaseStorage

All Implemented Interfaces:

DatabaseStorage, MMJdbc2NodeInterface, Storage

public class RelationalDatabaseStorage

extends SQL92DatabaseStorage

implements DatabaseStorage, MMJdbc2NodeInterface

RelationalDatabaseStorage implements the DatabaseStorage interface and the MMJdbc2NodeInterface for Ansi SQL 92 relational databases. This class extends AbstractDatabaseStorage to include methods for retrieving data from a relational database systems. It overrides the various update methods to allow for recursive updates on parent tables, the methods for storing and retrieving huge texts and bytefields, and teh methods for determining database key (for the object 'number' field).

Since:

MMBase-1.6

Version:

$Id: RelationalDatabaseStorage.java,v 1.4 2002/11/12 16:57:53 pierre Exp $

Author:

Pierre van Rooden

Fields inherited from class org.mmbase.storage.database.AbstractDatabaseStorage

mmb

Fields inherited from interface org.mmbase.storage.database.DatabaseStorage

KEY_FOREIGN, KEY_NONE, KEY_NOTNULL, KEY_PRIMARY, KEY_SECONDARY

Constructor Summary

RelationalDatabaseStorage()
Constructs the Ansi SQL database layer support class

Method Summary

protected boolean	commitObjectTable(MMObjectNode node, DatabaseTransaction trans) Commit this node to the object table.
boolean	commitToTable(MMObjectBuilder builder, MMObjectNode node, DatabaseTransaction trans) Commit this node to the specified builder table.
int	createKey(Transaction trans) Gives an unique number for a node to be inserted.
boolean	deleteFromTable(MMObjectBuilder builder, MMObjectNode node, DatabaseTransaction trans) Remove a node from the specified builder table.
protected boolean	deleteObjectTable(MMObjectNode node, DatabaseTransaction trans) Remove a node from the object table.
byte[]	getBytes(java.lang.String tableName, java.lang.String fieldname, int number) Get byte of a database blob
byte[]	getDBByte(java.sql.ResultSet rs, int idx) Get byte of a database blob
java.lang.String	getDBText(java.sql.ResultSet rs, int idx) Get text of a database blob
java.lang.String	getText(java.lang.String tableName, java.lang.String fieldname, int number) Get text from blob
int	insertIntoTable(MMObjectBuilder builder, MMObjectNode node, DatabaseTransaction trans) This method inserts a new object in a specified builder table.
protected int	insertObjectTable(MMObjectNode node, DatabaseTransaction trans) This method inserts a new object in the object table.
protected void	prepare() Prepares the database layer.
void	setDBByte(int i, java.sql.PreparedStatement stmt, byte[] bytes) Set byte array in database
void	setDBText(int i, java.sql.PreparedStatement stmt, java.lang.String body) Set text array in database
boolean	supportsExtendedTables() Returns whether this storage layer supports extended tables.

Methods inherited from class org.mmbase.storage.database.SQL92DatabaseStorage

addField, applyCreateScheme, changeField, commit, create, created, created, createObjectStorage, createSQL, delete, deleteSQL, drop, dropSQL, getBytes, getFieldsOrderCreate, getNode, getNodeType, getParentBuilder, getParentTableName, getText, init, insert, insertSQL, isAllowedParentBuilder, isParentField, loadExistingTables, loadFieldFromTable, loadSupportInformation, readBytesFromFile, removeField, selectSQL, setValuePreparedStatement, size, size, supportsRollback, updateSQL, updateStorage, writeBytesToFile

Methods inherited from class org.mmbase.storage.database.AbstractDatabaseStorage

applyForeignKeyScheme, applyKeyScheme, applyNotNullScheme, applyPrimaryKeyScheme, applyScheme, commit, constructFieldDefinition, constructFieldDefinition, create, createDatabaseTransaction, createDatabaseTransaction, createKey, createObjectStorage, createSQL, createTransaction, delete, deployDatabaseDocument, getBinaryFilePath, getCreateExtendedScheme, getCreateScheme, getFieldNameMap, getForeignKeyScheme, getFullTableName, getJDBC, getKeyScheme, getMaxDropSize, getNode, getNodeType, getNotNullScheme, getNumberString, getPrimaryKeyScheme, getStoreBinaryAsFile, getTypeMap, insert, mapToMMBaseFieldName, mapToTableFieldName, matchType, registerChanged, registerParentBuilder, selectSQL, selectSQL, selectSQL, setBinaryFilePath, setCreateExtendedScheme, setCreateScheme, setFieldNameMap, setForeignKeyScheme, setKeyScheme, setMaxDropSize, setNotNullScheme, setPrimaryKeyScheme, setStoreBinaryAsFile, setTypeMap

Methods inherited from class org.mmbase.storage.database.Support2Storage

commit, createObjectTable, decodeDBnodeField, decodeDBnodeField, getAllowedField, getConnection, getDBKey, getDisallowedField, getMMNodeSearch2SQL, getOTypeString, getOwnerString, getShortedByte, getShortedText, insert, removeNode, updateTable

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.mmbase.storage.database.DatabaseStorage

deployDatabaseDocument, getBinaryFilePath, getCreateExtendedScheme, getCreateScheme, getFieldNameMap, getForeignKeyScheme, getJDBC, getKeyScheme, getMaxDropSize, getNotNullScheme, getPrimaryKeyScheme, getStoreBinaryAsFile, getTypeMap, init, loadFieldFromTable, mapToMMBaseFieldName, mapToTableFieldName, registerChanged, setBinaryFilePath, setCreateExtendedScheme, setCreateScheme, setFieldNameMap, setForeignKeyScheme, setKeyScheme, setMaxDropSize, setNotNullScheme, setPrimaryKeyScheme, setStoreBinaryAsFile, setTypeMap, setValuePreparedStatement

Methods inherited from interface org.mmbase.storage.Storage

addField, changeField, commit, commit, create, create, created, createKey, createObjectStorage, createObjectStorage, createTransaction, delete, delete, drop, getBytes, getNode, getNode, getNodeType, getNodeType, getText, insert, insert, isAllowedParentBuilder, registerParentBuilder, removeField, size, supportsRollback, updateStorage

Methods inherited from interface org.mmbase.module.database.support.MMJdbc2NodeInterface

addField, changeField, commit, create, created, createObjectTable, decodeDBnodeField, decodeDBnodeField, drop, getAllowedField, getConnection, getDBKey, getDisallowedField, getMMNodeSearch2SQL, getNumberString, getOTypeString, getOwnerString, getShortedByte, getShortedText, init, insert, isAllowedParentBuilder, registerParentBuilder, removeField, removeNode, updateTable

Constructor Detail

RelationalDatabaseStorage

public RelationalDatabaseStorage()

Constructs the Ansi SQL database layer support class

Method Detail

prepare

protected void prepare()

Prepares the database layer. This code creates a 'numbertable' for MMBase to track number generation by the createKey(org.mmbase.storage.Transaction) method. Override this method if you use a different way of generating keys, or if you need to make other preparations for your database.

Overrides:

prepare in class SQL92DatabaseStorage

supportsExtendedTables

public boolean supportsExtendedTables()

Returns whether this storage layer supports extended tables.

Specified by:

supportsExtendedTables in interface DatabaseStorage

Overrides:

supportsExtendedTables in class SQL92DatabaseStorage

Returns:

boolean true if extended tables are supported

getText

public java.lang.String getText(java.lang.String tableName,
                                java.lang.String fieldname,
                                int number)

Get text from blob

Overrides:

getText in class SQL92DatabaseStorage

getBytes

public byte[] getBytes(java.lang.String tableName,
                       java.lang.String fieldname,
                       int number)

Get byte of a database blob

Overrides:

getBytes in class SQL92DatabaseStorage

getDBByte

public byte[] getDBByte(java.sql.ResultSet rs,
                        int idx)

Get byte of a database blob

Specified by:

getDBByte in interface MMJdbc2NodeInterface

Overrides:

getDBByte in class Support2Storage

getDBText

public java.lang.String getDBText(java.sql.ResultSet rs,
                                  int idx)

Get text of a database blob

Specified by:

getDBText in interface MMJdbc2NodeInterface

Overrides:

getDBText in class Support2Storage

setDBText

public void setDBText(int i,
                      java.sql.PreparedStatement stmt,
                      java.lang.String body)

Set text array in database

Overrides:

setDBText in class AbstractDatabaseStorage

setDBByte

public void setDBByte(int i,
                      java.sql.PreparedStatement stmt,
                      byte[] bytes)

Set byte array in database

Specified by:

setDBByte in interface MMJdbc2NodeInterface

Overrides:

setDBByte in class AbstractDatabaseStorage

createKey

public int createKey(Transaction trans)
              throws StorageException

Gives an unique number for a node to be inserted. This method will work with multiple mmbases

Specified by:

createKey in interface Storage

Overrides:

createKey in class AbstractDatabaseStorage

Parameters:

trans - the transaction to use for obtaining the key

Returns:

unique number

Throws:

StorageException - if an error occurred while obtaining the key

insertIntoTable

public int insertIntoTable(MMObjectBuilder builder,
                           MMObjectNode node,
                           DatabaseTransaction trans)
                    throws StorageException

This method inserts a new object in a specified builder table. Only fields with states of DBSTATE_PERSISTENT or DBSTATE_SYSTEM are stored in the database tables.

Overrides:

insertIntoTable in class SQL92DatabaseStorage

Parameters:

builder - the builder to store teh node in. This can be a parentbuilder of the node's actual builder

node - The node to insert

trans - the transaction to perform the insert in

Returns:

The (new) number for this node, or -1 if an error occurs.

Throws:

StorageException - if an error occurred during insert

insertObjectTable

protected int insertObjectTable(MMObjectNode node,
                                DatabaseTransaction trans)
                         throws StorageException

This method inserts a new object in the object table. Called by SQL92DatabaseStorage.insert(org.mmbase.module.core.MMObjectNode, org.mmbase.storage.Transaction) to maintain consistency.

Parameters:

node - The node to insert

trans - the transaction to perform the insert in

Returns:

The (new) number for this node, or -1 if an error occurs.

Throws:

StorageException - if an error occurred during insert

commitToTable

public boolean commitToTable(MMObjectBuilder builder,
                             MMObjectNode node,
                             DatabaseTransaction trans)
                      throws StorageException

Commit this node to the specified builder table.

Overrides:

commitToTable in class SQL92DatabaseStorage

Parameters:

builder - the builder to commit the node to. This can be a parentbuilder of the node's actual builder

node - The node to insert

trans - the transaction to perform the insert in

Returns:

true of succesful, false otherwise

Throws:

StorageException - if an error occurred during commit

commitObjectTable

protected boolean commitObjectTable(MMObjectNode node,
                                    DatabaseTransaction trans)
                             throws StorageException

Commit this node to the object table.

Parameters:

node - The node to insert

trans - the transaction to perform the insert in

Returns:

true of succesful, false otherwise

Throws:

StorageException - if an error occurred during commit

deleteFromTable

public boolean deleteFromTable(MMObjectBuilder builder,
                               MMObjectNode node,
                               DatabaseTransaction trans)
                        throws StorageException

Remove a node from the specified builder table.

Overrides:

deleteFromTable in class SQL92DatabaseStorage

Parameters:

builder - the builder to remove the node from. This can be a parentbuilder of the node's actual builder

node - The node to delete

trans - the transaction to perform the insert in

Throws:

StorageException - if an error occurred during delete

deleteObjectTable

protected boolean deleteObjectTable(MMObjectNode node,
                                    DatabaseTransaction trans)
                             throws StorageException

Remove a node from the object table.

Parameters:

node - The node to delete

trans - the transaction to perform the insert in

Throws:

StorageException - if an error occurred during delete