title: PostgreSQL 9.6.9 on Alpine Linux (arm32v6) in Docker container - how to install correct postgresql-contrib package?
body: <p>I need to install PostgreSQL 9.6.9 with uuid-ossp support in a Docker container on a 32-bit ARM system (its a QNAP NAS, CPU: Annapurna Labs Alpine AL-314).</p>
  
  <p>I found the <a href="https://hub.docker.com/r/arm32v6/postgres/" rel="nofollow noreferrer">arm32v6/postgres</a> images and installed <code>arm32v6/postgres:9.6.9-alpine</code>. This is working smoothly, but lacks the postgresql-contrib package. As far as I understand, I need to install postgresql-contrib to get uuid-ossp support.</p>
  
  <p>I opened a CLI in the container and tried:</p>
  
  <pre><code># apk update
  fetch http://dl-cdn.alpinelinux.org/alpine/v3.7/main/armhf/APKINDEX.tar.gz
  fetch http://dl-cdn.alpinelinux.org/alpine/v3.7/community/armhf/APKINDEX.tar.gz
  v3.7.0-215-g16971064c0 [http://dl-cdn.alpinelinux.org/alpine/v3.7/main]
  v3.7.0-207-gac61833f9b [http://dl-cdn.alpinelinux.org/alpine/v3.7/community]
  OK: 8879 distinct packages available
  # apk add postgresql-contrib=9.6.9-r0
  ERROR: unsatisfiable constraints:
    postgresql-contrib-10.4-r0:
      breaks: world[postgresql-contrib=9.6.9-r0]
  </code></pre>
  
  <p>How can I install the correct version of postgresql-contrib? Or can I just use postgresql-contrib-10.4-r0 with PostgreSQL 9.6.9?</p>