LibPQ on the Raspberry PI

General Usage
1

I have LibPQ working on a Windows machine. I am now trying to get it to work on a Raspberry PI 4. The RPI has 64 bit bookworm installed as Raspberry PI OS. It is up to date.

I installed Postgresql using the installation instructions at this site. This includes the installation instructions and the instructions for setting up the CLI.

Then going to a discourse discussion I included the steps on this discourse post.

When I type in either of the commands

conn = LibPQ.Connection("dbname=postgres")
conn = LibPQ.Connection("dbname=postgres user=jakez")

I get this error message

[error | LibPQ]: connection to server on socket "/tmp/.s.PGSQL.5432" failed: No such file or directory
        Is the server running locally and accepting connections on that socket?
ERROR: connection to server on socket "/tmp/.s.PGSQL.5432" failed: No such file or directory
        Is the server running locally and accepting connections on that socket?
Stacktrace:
 [1] error(logger::Memento.Logger, exc::LibPQ.Errors.PQConnectionError)
   @ Memento ~/.julia/packages/Memento/xnHxE/src/loggers.jl:463
 [2] handle_new_connection(jl_conn::LibPQ.Connection; throw_error::Bool)
   @ LibPQ ~/.julia/packages/LibPQ/CRtC5/src/connections.jl:127
 [3] LibPQ.Connection(str::String; throw_error::Bool, connect_timeout::Int64, options::Dict{…}, kwargs::@Kwargs{})
   @ LibPQ ~/.julia/packages/LibPQ/CRtC5/src/connections.jl:0
 [4] LibPQ.Connection(str::String)
   @ LibPQ ~/.julia/packages/LibPQ/CRtC5/src/connections.jl:265
 [5] top-level scope
   @ REPL[4]:1
Some type information was truncated. Use `show(err)` to see complete types.

I am not sure what to do next.
2

Found the problem. Postgres tends to be case insensitive, but the database name must be in lower case for the RPI, where it does not need to be for windows. I also needed to add the port and host to the DBInterface.connect command. The example is:

Works for Windows
dbread = "Test2"
DATABASE_USER = get(ENV, "LIBPQJL_DATABASE_USER", "postgres")
DATABASE_PASSWORD = Password
conn = DBInterface.connect(FunSQL.DB{LibPQ.Connection}, 
"dbname=$dbread user=$DATABASE_USER password=$DATABASE_PASSWORD")

Changes for RPI
dbread = "test2"
conn = DBInterface.connect(FunSQL.DB{LibPQ.Connection}, 
"dbname=$dbread user=$DATABASE_USER password=$DATABASE_PASSWORD
host=localhost port=5432")
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