Loading a PDW Region in APS - SQL Server Integration Services Design Patterns - page 247

Figure 8-4 . The Data Conversion Transformation Editor
Tip Wonder why we use a string length of 38 when converting a
UNIQUEIDENTIFIER to a CHAR ? This is because the global representation of a GUID
is {00000000-0000-0000-0000-000000000000} . The curly brackets are
stored implicitly in SQL Server for UNIQUEIDENTIFIER columns. Thus, during con-
version, Integration Services materializes the curly brackets for export to the destination
system. That is why, although a UNIQUEIDENTIFIER may look like it would only
consume 36 bytes, it actually requires 38 bytes to store in PDW.
The Data Destination
The next few tasks, which prepare the PDW appliance for receiving FactSales data,
will take place in SQL Server Data Tools—or just SSDT for short. Please refer to the
section, “Install SQL Server Data Tools for Visual Studio (SQL Server PDW),” in the
PDW documentation for more information on connecting to PDW from SSDT.
Before we go any further, we should discuss the use of a staging database . Al-
though it is not required, Microsoft recommends that you use a staging database during
incremental loads to reduce table fragmentation. When you use a staging database, the