Can I run an SQLite operation from Terminal?
Yes. You can use the /usr/bin/sqlite3 command line tool to modify the database. It ships, default, with OS X so you don't need to do anything other than open a Terminal window and then run:

cd path/to/quicken/storage/directory
sqlite3 &lt;quicken database file&gt;

SQLite version 3.7.13 2012-07-17 17:46:21
Enter ".help" for instructions
Enter SQL statements terminated with a ";"
sqlite&gt; UPDATE ZFIPAYEE SET ZNAME = replace(ZNAME,'DEBIT PURCHASE - ','');
sqlite&gt; .quit


You can do it all from one command line like this if you like:

sqlite3 &lt;quicken database file&gt; 'UPDATE ZFIPAYEE SET ZNAME = replace(ZNAME,\'DEBIT PURCHASE - \',\'\');'


That will open, modify and close your database file and return the prompt.

For more information on using the SQLite command line too see: http://www.sqlite.org/sqlite.html