Configuring SAP IQ as a Near-Line Storage Solution

Configuration Steps in SAP BW:

Creating a Database Connection

1. Call transaction DBCO and create a database connection to SAP IQ. For more details, see step 4 in SAP Note 1737415.

Creating Near-Line Storage Connections

1. Create a near-line storage connection. You can call this transaction in Customizing by choosing SAP Customizing Implementation Guide  SAP NetWeaver  Business Warehouse   General BW Settings  Edit Near-Line Storage Connections and in the Data Warehousing Workbench under Administration  Current Settings  Near-Line Storage Connections.

2. Choose New Entries.

3. Enter a name for the near-line storage connection. This name is then offered to you for selection when you create a data archiving process.

4. As the name, enter class CL_RSDA_SYB_CONNECTION.

5. Leave the Destination field empty.

6. Enter a connection string under Connection Parameters. The connection string generally comprises a list of name/value pairs, separated by a semi-colon. Each name/value pair must be entered as follows:

   <Name of the parameter>=<Value of the parameter>

   The following parameters are supported:

   • DBCON (required entry): The value of the parameter should be the name of the database connection that you created in the first step.

   • BACKUP_REQUEST_EVENT (optional):

     The value should be either DUMMY or the name of an event that has been defined in the SAP IQ database and which triggers a new data backup. If this parameter is entered, and all data has been copied to SAP IQ, the end of the write phase triggers this event. This makes it possible to perform data backup in SAP IQ at the same time as the verification phase. Before the actual deletion process begins, the system checks for a backup in SAP IQ. The deletion phase cannot continue until this has happened.

     A special event called DUMMY triggers an event in the SAP IQ database. It checks for a more recent data backup however before the data in the request is deleted from the BW database. The DUMMY event should therefore be used if database backups are detected before the data is deleted and the data backups are automatically created by the SAP IQ database.

     If the parameter is left out or does not contain any values, no event is triggered, and the system does not check for data backups. You should only choose this setting in non-productive systems.

   • BACKUP_WAIT_SEC (optional)

     If the BACKUP_REQUEST_EVENT has been specified, and no data backup is detected before the start of the deletion phase, the process waits for a period specified here in seconds. If no data backup is detected during this period, the archiving request terminates with error message RSDA_SYB197: "No new data backup since the end of the copy phase. The current data backup ID is still <backup ID> of <timestamp>." The parameters <backup ID> and <timestamp> refer to the columns bu_id and bu_time in the Sybase IQ system view SYSIQBACKUPHISTORY. All rows with the condition selective_type in (1,2) are taken into account. This excludes all data backups that only refer to read-only files. The archiving request only be restarted once the data backup has been created.

   • PACKET_SIZE_MB (optional)

     The package size of a single LOAD statement in MB. If this parameter is left out or does not contain any values, the package size of the LOAD statement is exactly the same as the package size of the FETCH of the online table. This is currently set to 20 MB. A package size greater than 2000 is ignored and replaced by 2000 MB.

7. Save your settings.

Configuration Steps in SAP IQ

These configuration steps in SAP IQ are optional in order to integrate an automated data backup mechanism.

1. Log on to SAP IQ with user DBA using Sybase Central or IQISQL.

2. Create an event that triggers a new data backup. As the name of the event, enter the name that you entered in step 6 for BACKUP_REQUEST_EVENT. The way the event is handled depends on your data backup and data recovery strategy.

   The following event definition shows a very simple strategy. Here, a data backup is always started whenever the event is triggered. The data backup files are stored in a directory in the database's Home directory. The name of the database forms part of the path name and of the file name.

                        CREATE EVENT BACKUP_REQUEST
   HANDLER
     BEGIN
       -- Declare and set unique filename          
       DECLARE filename varchar(255);
       SET filename = '../backup/' || db_name() || '/' || db_name() ||
                      '_' || dateformat(now(),'yyyymmdd_hhnnss.ssssss');
       -- Perform incremental backup
       BACKUP DATABASE FULL TO filename;
     END