split out file name from path in postgres

Question

I have a field that contains windows file paths, like so:

\\\\fs1\\foo\\bar\\snafu.txt
c:\\this\\is\\why\\i\\drink\\snafu.txt
\\\\fs2\\bippity\\baz.zip
\\\\f         


        

Answer 1

You can easily strip the path up to the last directory separator with an expression like

regexp_replace(path, '^.+[/\\]', '')

This will match the ocassional forward slashes produced by some software as well. Then you just count the remaining file names like

WITH files AS (
    SELECT regexp_replace(my_path, '^.+[/\\]', '') AS filename
    FROM my_table
)
SELECT filename, count(*) AS count
FROM files
GROUP BY filename
HAVING count(*) >= 2;