dbadmin=> SELECT c1, REGEXP_REPLACE(c1, '(?<=\, |^)(.+?)\, (?=(.+\, )?\1(\, |$))', '') FROM test;
c1 | regexp_replace
------------------------+----------------
A, B, B, A | B, A
A, B, C, A, T | B, C, A, T
A, B | A, B
D, A, B, C, C, D, D | A, B, C, D
Z, X, Z, X, A, A, A, Q | Z, X, A, Q
*, *, *, *, * | *
(6 rows)
Have Fun!
About the Author
Soniya Shah
Information Developer
Currently, a first year law student with a background in science and technology. Experienced technical writer, with specializations in software documentation, big data, blog development, and website development. I build user-centered content to communicate complex and technical information more easily.
I used to work for Vertica full time for about 3 years. I still work at Vertica part time while going to law school.
Update: Soniya is now doing her law internship, and no longer working at Vertica. Good luck, Soniya!
