LOB file reference variables

In a host application, you can use a file reference variable to insert a LOB or XML value from a file into a DB2® table. You can also use a file reference variable to select a LOB or XML value from a DB2 table into a file.

The file reference variables are BLOB_FILE, CLOB_FILE, or DBCLOB_FILE. For COBOL, the file reference variables are BLOB-FILE, CLOB-FILE, or DBCLOB-FILE.

When you use a file reference variable, you can select or insert an entire LOB or XML value without contiguous application storage to contain the entire LOB or XML value. LOB file reference variables move LOB or XML values from the database server to an application or from an application to the database server without going through the application's memory. Furthermore, LOB file reference variables bypass the host language limitation on the maximum size allowed for dynamic storage to contain a LOB value.

You can declare LOB or XML values as LOB file reference variables or LOB file reference arrays for applications that are written in C, COBOL, PL/I, and assembler. The LOB file reference variables do not contain LOB data; they represent a file that contains LOB data. Database queries, updates, and inserts can use file reference variables to store or retrieve column values. As with other host variables, a LOB file reference variable can have an associated indicator variable.