This applies to PC Other tables when Add columns to support LOBs has been selected.
At table build time, additional columns will be added to your table to allow the storage of BLOB and CLOB. For each BLOB or CLOB field, a tablename column will be added, with the initial value of NULL. When an insert or update of a table is carried out by LANSA, a tablename value will be stored in this column.
When reading rows back from the table, if the BLOB or CLOB is not NULL, but the tablename column is NULL (as LANSA did not do the insert, and has not updated the row), a random tablename will be generated. The tablename will have the extension .txt for a CLOB, and .bin for a BLOB, and will be unique in its directory.
If the tablename column has a value at read time, that tablename will be used when creating the table. This is a useful feature when you want to know what the tablename will be at read time.