Today I’ve been exposed to the world of SQL Loader. There is a process that runs on a daily basis that does the following:
1. Parse a text file and copy to a remote server
2. Use SQL Loader to append the contents of this file to a database table
3. A final process to concatenate 2 fields in the database after the insert has completed.
Step 3 is an unnecessary overhead that was introduced a while back. Steps 1 or 2 are the better areas for this fix to be implemented. Having never used SQL Loader it looked a more interesting learning experience, and heres some quick findings.
To read the value into a temporary store, use the BOUNDFILLER key word (apparently supported in Oracle 9+). However, with our implementation, then continue to process the columns in order, before finally coming back to insert the temp values into their relevant columns.
The text file looks roughly like this:
And the database table has the following columns
The SQL Loader to concatenate File Entry  and File Entry  is as follows:
Found plenty of examples on the Internet, but few made reference to the fields needing to be the final ones inserted.