|DB2 UDB now makes use of LOB location specifiers (LLSs) when importing, |exporting, and loading large object (LOB) information. This allows multiple |LOBs to be stored in a single file.
|An LLS is a string indicating where LOB data can be found within a file. |The format of the LLS is filename.ext.nnn.mmm/, where filename.ext is the name of the file that contains the LOB, nnn is the offset |of the LOB within the file (measured in bytes), and mmm is the |length of the LOB (in bytes). For example, an LLS of db2exp.001.123.456/ indicates that the lob is located in file db2exp.001, begins at an offset of 123 bytes into the file, |and is 456 bytes long. If the indicated size in the LLS is 0, the LOB is considered |to have a length of 0. If the length is -1, the LOB is considered to be NULL |and the file name and offset do not matter.
|When exporting data using the lobsinfile modifier, |the LOBs will not always be placed into separate files. There may be multiple |LOBs in each LOB file, and multiple LOB files per LOB path. The data file |will now contain LLS records instead of just file names.
|The import and load functions have also been changed to handle the changes |to the export function. When loading or importing data with the modified by lobsinfile option specified, LLSs will be expected for each |of the corresponding LOB columns. If something other than an LLS is encountered |for a LOB column, the database will treat it as a LOB file, and will load |the entire file as the LOB.
|There are three new IXF data types. These three types correspond to character |large objects (CLOBs), binary large objects (BLOBs), and double-byte character |large objects (DBCLOBs) when represented by LLSs. The values of these data |types are 964, 960, and 968 respectively.
|IXF files now require each LOB column to have its own D record. This is |created automatically by the export tool, but must be created manually if |you are using a third party utility to create the IXF files. Additionally, |an LLS is required for each LOB in the table, and not just the non-null LOBs. |If a LOB column is null, you must write an LLS representing a null LOB.