Regex matching beginning AND end strings

Well, the simple regex is this:

/^dbo\..*_fn$/

It would be better, however, to use the string manipulation functionality of whatever programming language you're using to slice off the first four and the last three characters of the string and check whether they're what you want.

^dbo\..*_fn$

This should work you.

If you're searching for hits within a larger text, you don't want to use ^ and $ as some other responders have said; those match the beginning and end of the text. Try this instead:

\bdbo\.\w+_fn\b

\b is a word boundary: it matches a position that is either preceded by a word character and not followed by one, or followed by a word character and not preceded by one. This regex will find what you're looking for in any of these strings:

dbo.functionName_fn
foo dbo.functionName_fn bar
(dbo.functionName_fn)

...but not in this one:

foodbo.functionName_fnbar

\w+ matches one or more "word characters" (letters, digits, or _). If you need something more inclusive, you can try \S+ (one or more non-whitespace characters) or .+? (one or more of any characters except linefeeds, non-greedily). The non-greedy +? prevents it from accidentally matching something like dbo.func1_fn dbo.func2_fn as if it were just one hit.