It consists of various components as mentioned above for processing of SQL statements from application users hosted on the top of HANA system.User requests via user interface/web browsers are sent to Web server hosting application which is communicated to SQL/MDX Processor in form of SQL queries. These are further segregated to different data engines in Index server according to query types.Session and Transaction Manager authorize SQL transactions and keep track of all the transactions either completed or running in the system.

In SAP HANA system, Session and Transaction Manager is responsible to keep track of all the executed transactions in HANA database. It includes both running transactions and closed transaction. When a transaction in HANA system is failed due to any reason, Transaction Manager informs corresponding engine to handle the error.Session Manager is responsible to manage open and closed sessions and to authorize all the transactions executed in HANA db.

SQL/MDX processor in HANA system processes all SQL and MDX statements executed in HANA system. SQL statements are generated for all the tables, schemas and MDX statements are raised for OLAP data processing. SQL stands for Structured Query Language and is Relational database language to manage two dimensional objects in HANA db.MDX stands for Multi Dimension Expression and is an OLAP language for processing MDX statements for multidimensional models.SQL/MDX Processor directs all the statement to relevant engines for processing and Engine optimization. It is used for authorization management in executing queries and Error handling while processing SQL/MDX statements.Following functions are ... Read More

Each HANA system contains multiple serves inside, which are responsible to perform different functions. Index Server is heart of SAP HANA system which contains SQL/MDX processor for handling SQL statements. Key component includes −Index ServerPreprocessorName ServerStatistics ServerHANA XS EngineSAP Host AgentSAP Solution Manager Diagnostic AgentSAP HANA Studio + RepositorySAP HANA Software Update Manager SUM

You can use following SQL statement for this −CREATE VIRTUAL TABLE ExampleCREATE VIRTUAL TABLE ABC.test_VT AT “ORCL_11G_WIN”.”NULL”.”OUTLN”.”Dept”;In this SQL statement, ABC.test_VT is Virtual table name“ORCL_11G_WIN”.”NULL”.”OUTLN”.”Dept”;- Remote location for creating Virtual table

When a remote source is added, you can see all the existing tables under that data source in HANA Studio. Next is to create virtual table mapping to data in the remote data sources in SAP HANA Studio. This can be done using GUI option.To add a table as a virtual table, you need to navigate to remote data source → Schema name → Table name → Right-click and Add as Virtual TableBelow shows how you can add a table as a Virtual Table using HANA Studio.

Note that while modifying or creating the property configuration file, only the property which is different from default value needs to be set. The mistake in property configuration file may result in incorrect action or result of data source.

When you create a new remote data source, SAP HANA Smart data access parse the respective property configuration file. With the use of config file- features, function mappings, data type mappings, and other properties will be linked together with the data source. This decides the communication between the SAP HANA and the data source.You can see part of the content of property_orcl.ini shown below −

You can check the following example to create a new remote source −CREATE REMOTE SOURCE TEST_11g ADAPTER “odbc” CONFIGURATION FILE ‘property_orcl.ini’ CONFIGURATION ‘DSN=oral11g_lnx’ WITH CREDENTIAL TYPE ‘PASSWORD’ USING ‘user=username;password=password′;In above SQL statement, can be one of −  ASEODBC, IQODBC,TDODBC, HIVEODBC,ODBC. Obviously, ASEODBC is for Sybase ASE as data source, IQODBC is for Sybase IQ, TDODBC is for Teradata Database, HIVEODBC is for Hadoop.

In SAP HANA SPS07, following data sources are supported under Smart data access −Sybase ASESAP Sybase IQTeradata 13.0 or higherApache Hadoop 2.3MSSQL 11Oracle 12cWhen you click on the Adapter name while creating a new remote data source, you can see a list of all supported databases.You can also see in the above snapshot that all databases use the ODBC connection for a remote data sources.