About the TDV DDL Feature
In addition to publishing to a database data service, you can use the TDV DDL (Data Definition Language) feature to manipulate tables in a physical data source. Also included in this topic are:
When your client application creates a table in a data source, it uses the connections and protocols established with TDV. A created table is immediately added to the TDV resource tree and can be manipulated like any other table object within TDV. TDV DDL CREATE TABLE supports the following features (as supported by the underlying data source):
• Column name specification
• Column type specification (after consulting the capabilities framework to determine type mapping appropriate to the data source)
• Column nullability specification
• Primary key specification
If your client application needs to DROP a table, the table is dropped from both the data source and the TDV resource tree directly. No re-introspection of the data source is needed to see the change within TDV.
This feature can be used to improve the performance of queries or reports, because it lets you create and drop temporary tables as needed to optimize actions.
Managing Data Type Mappings for the TDV DDL Feature
TDV can create tables in a wide variety of data source types, and so TDV consults its capabilities framework to determine the mappings between the data type name in the TDV query and the corresponding data type in the native data source. You can override the data type mappings, or specify new mappings, by defining custom data adapters for TDV. For more information, see
Adding and Removing Data Source Resources.
Based on testing, we recommend that you use the following data type mappings for custom adapters that you intend to use with MicroStrategy.
Database | Custom Data Type Mapping |
MySQL with MicroStrategy | FLOAT -> DOUBLE |
Oracle with MicroStrategy | DOUBLE -> NUMERIC |
TDV DDL Limitations
• If client applications are open and accessing data, and the temp table containers change, the updated settings might not be visible until the client applications sign in again. Temp tables created before the change are not deleted from the database.
• For data sources that make use of pass trough login, active temp tables might not get cleaned up during a TDV Server shutdown. TDV logs all those tables which it cannot clean up in the cs_server.log file at server startup.
Netezza DDL Creation Limitations
TDV cannot use DDL to create the following data types in Netezza data source tables:
• BINARY | • BLOB | • CLOB | • IMAGE | • LONG | • LONGRAW |
• NCLOB | • NTEXT | • TEXT | • TIMESTAMP | • VARBINARY | |