[Pkg-postgresql-public] Bug#852240: postgres: "apt-get purge" wipes clusters

[Tobias Wendorff]

Package: postgresql-9.6
Version: 9.6.1-2.pgdg80+1
Severity: minor
File: postgres

Dear Maintainer,

when removing PostgreSQL (9.5/9.6) using "apt-get purge", not only the
 configuration files get removed, but also all database files are wiped
off the disk.

Manpage of apt-get says:
> purge
>     purge is identical to remove except that packages are removed and
>     purged (any configuration files are deleted too).

I don't think, it's an expected behavior. There should be a message like:
"warning: while removing postgres, directory not empty so not removed"
This is common in Debian (schroot and others won't delete chroots).

-- System Information:
Debian Release: 8.7
  APT prefers stable-updates
  APT policy: (500, 'stable-updates'), (500, 'stable')
Architecture: amd64 (x86_64)

Kernel: Linux 3.16.0-4-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages postgresql-9.6 depends on:
ii  libc6                  2.19-18+deb8u7
ii  libgssapi-krb5-2       1.12.1+dfsg-19+deb8u2
ii  libldap-2.4-2          2.4.40+dfsg-1+deb8u2
ii  libpam0g               1.1.8-3.1+deb8u2
ii  libpq5                 9.6.1-2.pgdg80+1
ii  libssl1.0.0            1.0.1t-1+deb8u5
ii  libsystemd0            215-17+deb8u6
ii  libxml2                2.9.1+dfsg1-5+deb8u4
ii  locales                2.19-18+deb8u7
ii  postgresql-client-9.6  9.6.1-2.pgdg80+1
ii  postgresql-common      178.pgdg80+1
ii  ssl-cert               1.0.35
ii  tzdata                 2016j-0+deb8u1

Versions of packages postgresql-9.6 recommends:
ii  postgresql-contrib-9.6  9.6.1-2.pgdg80+1
ii  sysstat                 11.0.1-1

Versions of packages postgresql-9.6 suggests:
pn  locales-all  <none>

-- no debconf information