Smart Data Access - Basic Setup and Known Issues

Purpose

This blog will focus on basic setup of Smart Data Access (SDA) and then outline some problems that customers have encountered.  Some of the issues outlined in the troubleshooting section come directly from incidents that were created.

There is already a lot of information on Smart Data Access which this blog does not aim to replace.  Throughout the blog, I will reference links to other documentation that can cover the topics in more detail.

What is Smart Data Access (SDA)?

SDA allows customers to access data virtually from remote sources such as Hadoop, Oracle, Teradata, SQL Server, and more. Once a remote
connection to a data source is done we can virtually connect to the tables and query against is or use in data models as if it were data that resides in a SAP
HANA database.

This allows it so customers do not have to migrate or copy their data from other databases into a SAP HANA database.

How to Setup SDA?

Smart Data Access was introduced in SAP HANA SP6, so if you intend on using SDA be on at least this revision.

Prior to connecting to a remote database you will need to configure an ODBC connection from the server to the remote database. For
assistance on how to install the Database drivers on how to install the database drivers for SAP HANA Smart Data Access please refer to SAP note
1868702 and refer to the SAP HANA Learning  Academy videos

https://www.youtube.com/watch?v=BomjFbJ25vo&index=16&list=PLkzo92owKnVx_X9Qp-jonm3FCmo41Fkzm

Documentation on SDA can be found in the SAP HANA Admin guide chapter 6

http://help.sap.com/hana/SAP_HANA_Administration_Guide_en.pdf

Changes to SDA?

For information on what upgrades to SDA has occurred with each revision of SAP HANA please feel free to review the following

SP6 -> SP 7 delta

http://www.saphana.com/servlet/JiveServlet/previewBody/4296-102-7-9005/HANA_SPS07_NEW_SDA.pdf

SP7 -> SP 8 delta

http://www.saphana.com/docs/DOC-4681

What Remote Sources Are Supported (As of SP8)?

Hadoop

Teradata

SAP HANA

Oracle 12c

Sybase ASE

Sybase IQ

DB2 (SP8)

Microsoft SQL Server 2012

Apache Spark (SP8)

** Please note that you could connect to other databases via ODBC, but please note that we cannot guarantee that it will work. **

How To Add a Remote Source

Once you have configured your ODBC files to the external data source of your choosing you can setup a connection to that source in
Studio by doing the following (we are using Oracle in our example)

1. Expand your system -> Provisioning
   
2. Right click on the Remote Sources folder and select New Remote Source…
   
3. The main window pane will request you to enter in the connection information
4. Click on the Adapter Name drop down select the appropriate adapter (for this example we will select Oracle).  The main window pane will request
   you to enter in the connection information
   1. ASE – Adaptive Service Enterprise: version 15.7 ESD#4
   2. Teradata – version 13 and 14
   3. IQ – Version 15.4 ESD#3 and 16.0
   4. HANA – HANA revision 60 and up
   5. HADOOP – HDP 1.3 support added SP7
   6. Generic ODBC – This to connect to other databases that support ODBC protocol, however we do not guarantee that it will
      work
   7. Oracle – Oracle 12c support added in SP7
   8. MSSQL – Microsoft SQL Server ver11 support added in SP7
   9. Netezza – Netezza version 7 added in SP8
   10. DB2– DB2 UDB version 10.1 added in SP8
5. Fill in connection properties and credentials
6. Press the execute button to save this connection
   
   ** As an alternative, you can create a remote source through SQL using the following command: CREATE REMOTE SOURCE <Name>
   ADAPTER "odbc" CONFIGURATION FILE 'property_orcl.ini' CONFIGURATION 'DSN=<DSNNAME>' WITH CREDENTIAL TYPE 'PASSWORD' USING 'user=<USERNAME>;password=<Password>';
   
7. Press the Test Connection button to verify the connection to the source is successful
   
8. Under the Remote Source you will now see your connection
   
   

How To Access The Virtual Tables

1. After adding your New Remote Source, expand it  to see the users and the tables
   
   
2. Right click on the table you would like to access and select ‘Add as Virtual Table’
   
   
3. You will then choose the alias name and the schema you would like to add this virtual table
4. After hitting create you will get a confirmation message
   
   
   
5. Now you can check the schema you have chosen
   
6. If you select ‘Open Definition’
   
7. You will see under the ‘Type’ it says ‘Virtual’

Reported Problems

Description: After Restarting the HANA database, object privileges are lost

Resolution: This is resolved in Revision 75.  Documented in note: 2077504 - Smart Data
Access object privileges dropped from role after restarting HANA

Description: [08S01][unixODBC][SAP AG][LIBODBCHDBSO][HDBODBC] Communication link failure;-10709 Connect failed (no

reachable host left)

Resolution: This issue was caused by firewall blocking connectivity

Description: Issue connecting to Teradata
/opt/teradata/client/13.10/odbc_64/bin> ./tdxodbc: /usr/sap/odbc_drivers/unixODBC-2.3.2/DriverManager/.libs/libodbc.so: no version information available

(required by ./tdxodbc)

Resolution: tdxodbc is loading the incorrect libodbc.so library.  The $LD_LIBRARY_PATH environment variable should have the Teradata libraries appear before the UNIX ODBC Driver Manager libraries

Descritpion: Numeric overflow when to execute query on virtual table.
Error will look like:

com.sap.dataexplorer.core.dataprovider.DataProviderException:
Error: [314]: numeric overflow: 5.00 at

com.sap.ndb.studio.bi.datapreview.handler.DataPreviewQueryExecutor.executeQuery(DataPreviewQueryExecutor.java:192)at

com.sap.dataexplorer.ui.profiling.ProfilingComposite$12.run

Resolution: This issue is resolved in Revision 74.

Description: The GROUP BY &  Aggregation is not pushed down to the remote SDA source

using graphical calculation view.
Remote Source: This incident was reported with IQ
Resolution: HANA will not be able to push down aggregate functions to IQ via SDA until HANA

SPS9

Description: After configuration an Oracle Remote Source, the "Adapter Name" will switch to MSSQL (Generic ODBC)
Resolution: This issue simply a display issue.  It will still use the correct Oracle Adapters. This issue has been reported to development, but not currently scheduled to be fixed.

Description: After changing parameters of the SDA connection, the virtual tables disappear:
Remote Source: IQ 16.03
Solution: Edit the remote source parameters using "ALTER REMOTE SOURCE <remote_source_name>"

Description: SQL Server nvarchar(max) fields don't work with Smart Data Access.  Error:

SAP DBTech JDBC: [338]: zero-length columns are not allowed: LONGTEXT: line 1 col 209 (at pos 208)

Resolution: Planned to be fixed in SP09

** MORE issues will be updated at the bottom **

Authors

Man-Ted Chan

Jimmy Yang

Man-Ted Chan