diff --git a/README.md b/README.md
index a5f85cf..8082995 100644
--- a/README.md
+++ b/README.md
@@ -2,4 +2,7 @@ This is a build variant with PostgreSQL including [count_bits](https://github.co
 
 There are no other differences with `static-dockerhub` setup.
 
-Look here for more information: https://git.tt-rss.org/fox/ttrss-docker-compose/src/static-dockerhub/README.md
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+Look here for more information: https://git.tt-rss.org/fox/ttrss-docker-compose/src/static-dockerhub/README.md
+
+Q: How do I create functions on existing database?
+A: `docker-compose exec --user postgres db sh -c "cd /opt/count-bits ; make create_functions"`
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