com.ibm.websphere.rsadapter

Class MicrosoftSQLServerDataStoreHelper

java.lang.Object

com.ibm.websphere.rsadapter.GenericDataStoreHelper

com.ibm.websphere.rsadapter.MicrosoftSQLServerDataStoreHelper

All Implemented Interfaces:

DataStoreHelper

public class MicrosoftSQLServerDataStoreHelper
extends GenericDataStoreHelper

MicrosoftSQLServerDataStoreHelper is provided as an implementation of the DataStoreHelper interface to enable connectivity to Microsoft SQL Server via the Microsoft SQL Server JDBC Driver. If you have additional requirements with the Microsoft SQL Server JDBC Driver or the Microsoft SQL Server database, you should consider subclassing this implementation.
Note: This class and its methods cannot be called or referenced directly by applications.

SQLException mappings specific to the MicrosoftSQLServerDataStoreHelper are the following:

Error Code	SQL State	PortableSQLException subclass
230		StaleConnectionException.class
2627		DuplicateKeyException.class
6002		StaleConnectionException.class

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String[]	LOCK_OWNER_TPYES
static java.lang.String[]	LOCK_REQUEST_MODES
static java.lang.String[]	LOCK_REQUEST_STATUSES
static java.lang.String[]	RESOURCE_TYPES

Fields inherited from class com.ibm.websphere.rsadapter.GenericDataStoreHelper

customDefinedWasDefaultIsoLevel, defaultQueryTimeout, EOLN, genErrorMap, resBundle, tranErrorList

Fields inherited from interface com.ibm.websphere.rsadapter.DataStoreHelper

CLOUDSCAPE_HELPER, CLOUDSCAPE_NETWORK_SERVER_HELPER, CONNECTJDBC_HELPER, CUSTOM_HELPER, DATADIRECT_HELPER, DB2_390_HELPER, DB2_390_LOCAL_HELPER, DB2_400_HELPER, DB2_HELPER, DB2_UNIVERSAL_HELPER, DERBY_HELPER, DERBY_NETWORK_SERVER_HELPER, FIRST_TIME_CALLED, GENERIC_HELPER, INFORMIX_HELPER, INFORMIX_JCC_HELPER, MSSQL_HELPER, ORACLE_10G_HELPER, ORACLE_11G_HELPER, ORACLE_HELPER, POTENTIAL_DEADLOCK, POTENTIAL_LOST_UPDATE, PROXY_DS_HELPER, SEQUELINK_HELPER, SUBJECT, SYBASE_HELPER, SYBASE11_HELPER, TX_REPEATABLE_READ_FORUPDATE, TX_SERIALIZABLE_FORUPDATE, UNDEFINED_HELPER, UNDEFINED_ISOLATOIN_LEVEL, UPDATE_ON_READONLY

Constructor Summary

Constructors

Constructor and Description
MicrosoftSQLServerDataStoreHelper(java.util.Properties props) This MicrosoftSQLServerDataStoreHelper constructor creates a new MicrosoftSQLServerDataStoreHelper based on the DataStoreHelper properties provided.

Method Summary

Methods

Modifier and Type	Method and Description
void	doStatementCleanup(java.sql.PreparedStatement stmt) This method cleans up a statement before the statement is returned to the statement cache.
int	getIsolationLevel(AccessIntent intent) This method determines the transaction isolation level based on the specified AccessIntent.
int	getResultSetConcurrency(AccessIntent intent) This method determines the result set concurrency based on the specified AccessIntent.
java.lang.String	showLockInfo(java.util.Properties props) This method returns lock information for Microsoft SQL Server.

Methods inherited from class com.ibm.websphere.rsadapter.GenericDataStoreHelper

calcPartitionNumber, doConnectionCleanup, doConnectionCleanupPerCloseConnection, doConnectionCleanupWithValidCheck, doConnectionSetup, doConnectionSetupPerGetConnection, doConnectionSetupPerTransaction, findMappingClass, getLockType, getMetaData, getPasswordForUseWithTrustedContextWithAuthentication, getPrintWriter, getResultSetType, getXAExceptionContents, hasLostUpdateOrDeadLockOccurred, isBatchUpdateSupportedWithAccessIntent, isConnectionError, isDuplicateKey, isTransientConnectionError, mapException, modifyXAFlag, setConfig, setUserDefinedMap

Methods inherited from class java.lang.Object

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

Field Detail

RESOURCE_TYPES

public static final java.lang.String[] RESOURCE_TYPES

LOCK_REQUEST_STATUSES

public static final java.lang.String[] LOCK_REQUEST_STATUSES

LOCK_OWNER_TPYES

public static final java.lang.String[] LOCK_OWNER_TPYES

LOCK_REQUEST_MODES

public static final java.lang.String[] LOCK_REQUEST_MODES

Constructor Detail

MicrosoftSQLServerDataStoreHelper

public MicrosoftSQLServerDataStoreHelper(java.util.Properties props)

This MicrosoftSQLServerDataStoreHelper constructor creates a new MicrosoftSQLServerDataStoreHelper based on the DataStoreHelper properties provided. All implementations inheriting from a data store helper must supply this same list of properties to their super class by invoking the constructor of their super class with the list of properties.

Parameters:

props - DataStoreHelper properties.

Method Detail

doStatementCleanup

public void doStatementCleanup(java.sql.PreparedStatement stmt)
                        throws java.sql.SQLException

This method cleans up a statement before the statement is returned to the statement cache. This method is called only for statements that are cached. It is called only if at least one of the following statement properties has changed:

• cursorName
• fetchDirection
• maxFieldSize
• maxRows
• queryTimeout
• responseBuffering

MicrosoftSQLServerDataStoreHelper resets all of the properties listed above.

The following operations do not need to be included in the statement cleanup since they are automatically performed by the application server when caching statements,

• setFetchSize(0)
• clearParameters()
• clearWarnings()

A helper class implementing this method may choose to do additional cleanup for the statement. However, this should never include closing the statement, since the statement is intended to be cached.

Specified by:

doStatementCleanup in interface DataStoreHelper

Overrides:

doStatementCleanup in class GenericDataStoreHelper

Parameters:

stmt - the PreparedStatement.

Throws:

java.sql.SQLException - if an error occurs cleaning up the statement.

getIsolationLevel

public int getIsolationLevel(AccessIntent intent)
                      throws javax.resource.ResourceException

This method determines the transaction isolation level based on the specified AccessIntent. If the AccessIntent parameter is null, the following default value is returned: Connection.TRANSACTION_REPEATABLE_READ.

In the case where an AccessIntent is specified, MicrosoftSQLServerDataStoreHelper computes the transaction isolation level as follows:

• If the concurrency control is AccessIntent.CONCURRENCY_CONTROL_OPTIMISTIC then a transaction isolation level of Connection.TRANSACTION_READ_COMMITTED is returned.

• If the concurrency control is AccessIntent.CONCURRENCY_CONTROL_PESSIMISTIC and the access type is AccessIntent.ACCESS_TYPE_READ then a transaction isolation level of Connection.TRANSACTION_REPEATABLE_READ is returned.

• If the concurrency control is AccessIntent.CONCURRENCY_CONTROL_PESSIMISTIC and the access type is AccessIntent.ACCESS_TYPE_UPDATE then the transation isolation level is determined from the following table based on the pessimistic update lock hint.

  pessimistic update lock hint	transaction isolation level
  AccessIntent.PESSIMISTIC_UPDATE_LOCK_HINT_NONE AccessIntent.PESSIMISTIC_UPDATE_LOCK_HINT_WEAKEST_LOCK_AT_LOAD	Connection.TRANSACTION_REPEATABLE_READ
  AccessIntent.PESSIMISTIC_UPDATE_LOCK_HINT_NOCOLLISION	Connection.TRANSACTION_READ_COMMITTED
  AccessIntent.PESSIMISTIC_UPDATE_LOCK_HINT_EXCLUSIVE	Connection.TRANSACTION_SERIALIZABLE

Specified by:

getIsolationLevel in interface DataStoreHelper

Overrides:

getIsolationLevel in class GenericDataStoreHelper

Parameters:

intent - An AccessIntent

Returns:

A transaction isolation level appropriate for the specified AccessIntent.

Throws:

javax.resource.ResourceException - If a transaction isolation level cannot be determined from the AccessIntent.

See Also:

AccessIntent, Connection

getResultSetConcurrency

public int getResultSetConcurrency(AccessIntent intent)
                            throws javax.resource.ResourceException

This method determines the result set concurrency based on the specified AccessIntent. MicrosoftSQLServerDataStoreHelper returns java.sql.ResultSet.CONCUR_UPDATABLE if the access type of the AccessIntent is AccessIntent.ACCESS_TYPE_UPDATE and the concurrency control is AccessIntent.CONCURRENCY_CONTROL_PESSIMISTIC and the update lock hint is either AccessIntent.PESSIMISTIC_UPDATE_LOCK_HINT_EXCLUSIVE or AccessIntent.PESSIMISTIC_UPDATE_LOCK_HINT_NONE. In all other cases, java.sql.ResultSet.CONCUR_READ_ONLY is returned.

Specified by:

getResultSetConcurrency in interface DataStoreHelper

Overrides:

getResultSetConcurrency in class GenericDataStoreHelper

Parameters:

intent - An AccessIntent.

Returns:

A result set concurrency constant defined on java.sql.ResultSet.

Throws:

javax.resource.ResourceException - If a result set concurrency cannot be determined from the AccessIntent.

See Also:

AccessIntent, ResultSet

showLockInfo

public final java.lang.String showLockInfo(java.util.Properties props)
                                    throws java.lang.Exception

This method returns lock information for Microsoft SQL Server. The props parameter can include the following properties:

1. user user name that has a DBA authority. If not specified, a default value of "sa" is used.
2. password the password corresponding to the user name. If not specified, a default value of "" (empty string) is used.
3. serverName the server name where the Microsoft SQL Server database resides.
4. portNumber the port where Microsoft SQL Server is listening.

Overrides:

showLockInfo in class GenericDataStoreHelper

Parameters:

props - properties containing information needed to connect to the database.

Returns:

the lock information.

Throws:

java.lang.Exception - if an error occurs while collecting the lock information.