LOB Type Mapping

TimesTen supports the CLOB, NCLOB, and BLOB data types. However, currently the ttLoadFromOracle() built-in cannot load data into these types in TimesTen.

As a result, the LoadData.sql script does not generate the load commands for tables that include these columns. If you need to load data into these columns, map the Oracle data types to the TimesTen VARCHAR2, NVARCHAR2, or VARBINARY data types.

Type mapping is applied to Oracle database columns of type CLOB, NCLOB, and BLOB and is controlled by the lob field in the –typeMap command line option.

The lob field accepts any one of the following values:
Values Description
0 No mapping applies; CLOB, NCLOB, and BLOB columns are mapped to the same type in TimesTen. If a table contains columns of these data types, the generated LoadData.sql script does not load data from the corresponding Oracle table.
1 This is the default value. The LOB columns are mapped as follows:
  • CLOB to VARCHAR2(4194304)
  • NCLOB to NVARCHAR2(2097152)
  • BLOB to VARBINARY(4194304)

In addition, if variable length type optimization is specified (var=1) then it is also applied.