How do you run PostgreSQL query on Command Prompt?

@echo off
set REPORTNAME=%1
set timestamp=%date:~-4%%date:~4,2%%date:~7,2%_%time:~0,2%%time:~3,2%%time:~6,2%
set PGPASSWORD=<password>
"C:\Program Files (x86)\pgAdmin III\1.16\psql" -A -h %REPORTNAME% -U <UserName> -d <DatabaseName> -F , --pset footer -c "<Query>" -o "%REPORTNAME%_%timestamp%.csv"

How do you execute PostgreSQL scripts whose names start with 'p_'?

my $path = 'C:\TestSQL';

my @scripts = `dir /B /s $path`;

foreach my $psqlfile (@scripts) {
   if ( $psqlfile =~ /^(.+\\p\_[^\\]+\.sql)\s*$/i ) {
        `psql -q -h <Hostname> -p <Port> -d <Database> -U <Username> -f $psqlfile.sql -o outputfile`;
   }
}

How do you execute UNIX command in PostgreSQL prompt?

\! <command>

How do you connect to PostgreSQL in UNIX?

psql -h <Host> -d <Database> -U <User> -W -p <PortNo>

where,
-W = prompts for password to be typed.

How do you select 10 random rows in PostgreSQL?

SELECT *
FROM <TableName>
ORDER BY RANDOM()
LIMIT 10

How do you select top N records in PostgreSQL?

SELECT *
FROM <TableName>
LIMIT N;