org.apache.torque.adapter
Class DBDB2App

java.lang.Object
  org.apache.torque.adapter.AbstractDBAdapter
      org.apache.torque.adapter.DBDB2App

All Implemented Interfaces:

java.io.Serializable, DB, IDMethod

Direct Known Subclasses:

DBDB2400, DBDB2Net

public class DBDB2App
extends AbstractDBAdapter

This is used to connect via the Application-Driver to DB2 databases. http://www-306.ibm.com/software/data/db2/

Version:

$Id: DBDB2App.java 473821 2006-11-11 22:37:25Z tv $

Author:

Hakan Tandogan, Augustin Vidovic

See Also:

Serialized Form

Field Summary

Fields inherited from interface org.apache.torque.adapter.DB

ADAPTER_KEY, DRIVER_KEY, LIMIT_STYLE_DB2, LIMIT_STYLE_MYSQL, LIMIT_STYLE_NONE, LIMIT_STYLE_ORACLE, LIMIT_STYLE_POSTGRES, LIMIT_STYLE_SYBASE

Fields inherited from interface org.apache.torque.adapter.IDMethod

AUTO_INCREMENT, ID_BROKER, NATIVE, NO_ID_METHOD, SEQUENCE

Constructor Summary

protected

DBDB2App() Empty constructor.

Method Summary

void	generateLimits(Query query, int offset, int limit) Build DB2 (OLAP) -style query with limit or offset.
java.lang.String	getIDMethodSQL(java.lang.Object obj) Returns SQL used to get the most recently inserted primary key.
java.lang.String	getIDMethodType() Returns the constant from the IDMethod interface denoting which type of primary key generation method this type of RDBMS uses.
int	getLimitStyle() Deprecated. This should not be exposed to the outside
java.lang.String	ignoreCase(java.lang.String in) This method is used to ignore case.
void	lockTable(java.sql.Connection con, java.lang.String table) Locks the specified table.
boolean	supportsNativeLimit() Return true for DB2
boolean	supportsNativeOffset() Return true for DB2
java.lang.String	toUpperCase(java.lang.String in) This method is used to ignore case.
void	unlockTable(java.sql.Connection con, java.lang.String table) Unlocks the specified table.

Methods inherited from class org.apache.torque.adapter.AbstractDBAdapter

escapeText, getBooleanString, getDateString, getFunctionClass, getStringDelimiter, ignoreCaseInOrderBy, useEscapeClauseForLike, useIlike

Methods inherited from class java.lang.Object

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

Constructor Detail

DBDB2App

protected DBDB2App()

Empty constructor.

Method Detail

toUpperCase

public java.lang.String toUpperCase(java.lang.String in)

This method is used to ignore case.

Specified by:

toUpperCase in interface DB

Specified by:

toUpperCase in class AbstractDBAdapter

Parameters:

in - The string to transform to upper case.

Returns:

The upper case string.

ignoreCase

public java.lang.String ignoreCase(java.lang.String in)

This method is used to ignore case.

Specified by:

ignoreCase in interface DB

Specified by:

ignoreCase in class AbstractDBAdapter

Parameters:

in - The string whose case to ignore.

Returns:

The string in a case that can be ignored.

getIDMethodType

public java.lang.String getIDMethodType()

Description copied from class: AbstractDBAdapter

Returns the constant from the IDMethod interface denoting which type of primary key generation method this type of RDBMS uses.

Specified by:

getIDMethodType in interface DB

Specified by:

getIDMethodType in class AbstractDBAdapter

Returns:

IDMethod constant

See Also:

DB.getIDMethodType()

getIDMethodSQL

public java.lang.String getIDMethodSQL(java.lang.Object obj)

Description copied from class: AbstractDBAdapter

Returns SQL used to get the most recently inserted primary key. Databases which have no support for this return null.

Specified by:

getIDMethodSQL in interface DB

Specified by:

getIDMethodSQL in class AbstractDBAdapter

Parameters:

obj - Information used for key generation.

Returns:

The most recently inserted database key.

See Also:

DB.getIDMethodSQL(Object obj)

lockTable

public void lockTable(java.sql.Connection con,
                      java.lang.String table)
               throws java.sql.SQLException

Locks the specified table.

Specified by:

lockTable in interface DB

Specified by:

lockTable in class AbstractDBAdapter

Parameters:

con - The JDBC connection to use.

table - The name of the table to lock.

Throws:

java.sql.SQLException - No Statement could be created or executed.

unlockTable

public void unlockTable(java.sql.Connection con,
                        java.lang.String table)
                 throws java.sql.SQLException

Unlocks the specified table.

Specified by:

unlockTable in interface DB

Specified by:

unlockTable in class AbstractDBAdapter

Parameters:

con - The JDBC connection to use.

table - The name of the table to unlock.

Throws:

java.sql.SQLException - No Statement could be created or executed.

getLimitStyle

public int getLimitStyle()

Deprecated. This should not be exposed to the outside

This method is used to check whether the database supports limiting the size of the resultset.

Specified by:

getLimitStyle in interface DB

Overrides:

getLimitStyle in class AbstractDBAdapter

Returns:

LIMIT_STYLE_DB2.

supportsNativeLimit

public boolean supportsNativeLimit()

Return true for DB2

Specified by:

supportsNativeLimit in interface DB

Overrides:

supportsNativeLimit in class AbstractDBAdapter

Returns:

True if the database natively supports limiting the size of the resultset.

See Also:

AbstractDBAdapter.supportsNativeLimit()

supportsNativeOffset

public boolean supportsNativeOffset()

Return true for DB2

Specified by:

supportsNativeOffset in interface DB

Overrides:

supportsNativeOffset in class AbstractDBAdapter

Returns:

True if the database natively supports returning results starting at an offset position other than 0.

See Also:

AbstractDBAdapter.supportsNativeOffset()

generateLimits

public void generateLimits(Query query,
                           int offset,
                           int limit)

Build DB2 (OLAP) -style query with limit or offset. If the original SQL is in variable: query then the requlting SQL looks like this:

 SELECT B.* FROM (
          SELECT A.*, row_number() over() as TORQUE$ROWNUM FROM (
                  query
          ) A
     ) B WHERE B.TORQUE$ROWNUM > offset AND B.TORQUE$ROWNUM
     <= offset + limit
 

Specified by:

generateLimits in interface DB

Overrides:

generateLimits in class AbstractDBAdapter

Parameters:

query - The query to modify

offset - the offset Value

limit - the limit Value