In releases of the .NET Data Provider for Teradata earlier than 15.0, a Large Object (LOB) was always sent to a Teradata Database using Deferred mode. In this mode, the Teradata Provider creates a LOB identifier and sends it to the Teradata Database in place of the data of the LOB. The Teradata Database will respond back and request that the data for the LOB to be sent. The database will continue to request the data of the LOB until the Data Provider indicates that all the data of the LOB has been sent.
This interaction between the Data Provider and Teradata Database can be inefficient if there are several LOB parameters in a request that are small enough to be included in the data buffer that is sent to the database.
This inefficiency has been addressed in the Teradata Database 15.0 release with the introduction of SLOB. SLOB will enable the Teradata Provider to include small LOBs in the data buffer that is sent to the database. Sending these LOBs as SLOBs reduces the number of send and receive interactions between the Data Provider and Teradata Database by at least one for each LOB whose data can be included in the data buffer.
The .NET Data Provider for Teradata 15.0 release will automatically take advantage of the SLOB capability when connected to a Teradata Database 15.0 release or later.
LOBs will be In-Lined when the Data Provider is connected to a Teradata Database 14.0 or 14.10. The Data Provider will send LOBs using deferred mode for any release earlier than 14.0. In-Lining is automatically performed when the Teradata Database does not support the SLOB capability.
When a LOB is In-Lined, its data must appear in the data buffer in the order that its parameter was specified in the parameter list. When a batch is sent (using TdDataAdapter), the provider will In-Line the same LOB in each parameter row in the batch.