Re: Would it be possible to add functions to tab-completion in psql?

On 8/16/22 08:01, hubert depesz lubaczewski wrote:

On Tue, Aug 16, 2022 at 07:42:27AM -0500, Ron wrote:

On 8/16/22 07:28, hubert depesz lubaczewski wrote:

Hi,
As a dba I have to, very often, query system functions, starting with
pg_last_xact_replay_timestamp and pg_current_wal_lsn.

Would it be possible/hard/expensive, to change tab-completion so that:

select pg_<tab> would work?

It does, in the psql 9.6 and 12 that I installed from it's native
repositories, and the psql 12 installed from RHEL 7/8 native repositories.

Hmm .. I'm on Pg 16, linked with readline, and pressing tab after

Pg 16??

select pg_
just produces new prompt:

https://asciinema.org/a/A8w16KhXF7bK4iz7hE7iyyo0D

Can you please show me this working, with "which psql", and "ldd $(
which psql )" using asciinema?

$ alias psql12
alias psql12='/usr/lib/postgresql/12/bin/psql -p5433'

$ psql12
psql (12.11 (Ubuntu 12.11-1.pgdg18.04+1))
Type "help" for help.

postgres=# select * from pg_<tab>
Display all 130 possibilities? (y or n)


$ ldd /usr/lib/postgresql/12/bin/psql
    linux-vdso.so.1 (0x00007ffe9dfc3000)
    libpq.so.5 => /usr/lib/x86_64-linux-gnu/libpq.so.5 (0x00007f40d0cc0000)
    libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f40d0aa0000)
    libedit.so.2 => /usr/lib/x86_64-linux-gnu/libedit.so.2 (0x00007f40d0868000)
    librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00007f40d0660000)
    libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f40d02c0000)
    libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f40cfec8000)
    libssl.so.1.1 => /usr/lib/x86_64-linux-gnu/libssl.so.1.1 (0x00007f40cfc38000)
    libcrypto.so.1.1 => /usr/lib/x86_64-linux-gnu/libcrypto.so.1.1 (0x00007f40cf768000)
    libgssapi_krb5.so.2 => /usr/lib/x86_64-linux-gnu/libgssapi_krb5.so.2 (0x00007f40cf518000)
    libldap_r-2.4.so.2 => /usr/lib/x86_64-linux-gnu/libldap_r-2.4.so.2 (0x00007f40cf2c0000)
    /lib64/ld-linux-x86-64.so.2 (0x00007f40d11c0000)
    libtinfo.so.5 => /lib/x86_64-linux-gnu/libtinfo.so.5 (0x00007f40cf090000)
    libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f40cee88000)
    libkrb5.so.3 => /usr/lib/x86_64-linux-gnu/libkrb5.so.3 (0x00007f40cebb0000)
    libk5crypto.so.3 => /usr/lib/x86_64-linux-gnu/libk5crypto.so.3 (0x00007f40ce978000)
    libcom_err.so.2 => /lib/x86_64-linux-gnu/libcom_err.so.2 (0x00007f40ce770000)
    libkrb5support.so.0 => /usr/lib/x86_64-linux-gnu/libkrb5support.so.0 (0x00007f40ce560000)
    liblber-2.4.so.2 => /usr/lib/x86_64-linux-gnu/liblber-2.4.so.2 (0x00007f40ce350000)
    libresolv.so.2 => /lib/x86_64-linux-gnu/libresolv.so.2 (0x00007f40ce130000)
    libsasl2.so.2 => /usr/lib/x86_64-linux-gnu/libsasl2.so.2 (0x00007f40cdf10000)
    libgssapi.so.3 => /usr/lib/x86_64-linux-gnu/libgssapi.so.3 (0x00007f40cdcc8000)
    libgnutls.so.30 => /usr/lib/x86_64-linux-gnu/libgnutls.so.30 (0x00007f40cd960000)
    libkeyutils.so.1 => /lib/x86_64-linux-gnu/libkeyutils.so.1 (0x00007f40cd758000)
    libheimntlm.so.0 => /usr/lib/x86_64-linux-gnu/libheimntlm.so.0 (0x00007f40cd548000)
    libkrb5.so.26 => /usr/lib/x86_64-linux-gnu/libkrb5.so.26 (0x00007f40cd2b8000)
    libasn1.so.8 => /usr/lib/x86_64-linux-gnu/libasn1.so.8 (0x00007f40cd010000)
    libhcrypto.so.4 => /usr/lib/x86_64-linux-gnu/libhcrypto.so.4 (0x00007f40ccdd8000)
    libroken.so.18 => /usr/lib/x86_64-linux-gnu/libroken.so.18 (0x00007f40ccbc0000)
    libz.so.1 => /lib/x86_64-linux-gnu/libz.so.1 (0x00007f40cc9a0000)
    libp11-kit.so.0 => /usr/lib/x86_64-linux-gnu/libp11-kit.so.0 (0x00007f40cc670000)
    libidn2.so.0 => /usr/lib/x86_64-linux-gnu/libidn2.so.0 (0x00007f40cc450000)
    libunistring.so.2 => /usr/lib/x86_64-linux-gnu/libunistring.so.2 (0x00007f40cc0d0000)
    libtasn1.so.6 => /usr/lib/x86_64-linux-gnu/libtasn1.so.6 (0x00007f40cbeb8000)
    libnettle.so.6 => /usr/lib/x86_64-linux-gnu/libnettle.so.6 (0x00007f40cbc80000)
    libhogweed.so.4 => /usr/lib/x86_64-linux-gnu/libhogweed.so.4 (0x00007f40cba48000)
    libgmp.so.10 => /usr/lib/x86_64-linux-gnu/libgmp.so.10 (0x00007f40cb7c0000)
    libwind.so.0 => /usr/lib/x86_64-linux-gnu/libwind.so.0 (0x00007f40cb590000)
    libheimbase.so.1 => /usr/lib/x86_64-linux-gnu/libheimbase.so.1 (0x00007f40cb380000)
    libhx509.so.5 => /usr/lib/x86_64-linux-gnu/libhx509.so.5 (0x00007f40cb130000)
    libsqlite3.so.0 => /usr/lib/x86_64-linux-gnu/libsqlite3.so.0 (0x00007f40cae20000)
    libcrypt.so.1 => /lib/x86_64-linux-gnu/libcrypt.so.1 (0x00007f40cabe8000)
    libffi.so.6 => /usr/lib/x86_64-linux-gnu/libffi.so.6 (0x00007f40ca9e0000)