1.6. Example Program

Example 1-1. pgtcl Example Program

# getDBs :
#   get the names of all the databases at a given host and port number
#   with the defaults being the localhost and port 5432
#   return them in alphabetical order
proc getDBs { {host "localhost"} {port "5432"} } {
    # datnames is the list to be result
    set conn [pg_connect template1 -host $host -port $port]
    set res [pg_exec $conn "SELECT datname FROM pg_database ORDER BY datname;"]
    set ntups [pg_result $res -numTuples]
    for {set i 0} {$i < $ntups} {incr i} {
        lappend datnames [pg_result $res -getTuple $i]
    }
    pg_result $res -clear
    pg_disconnect $conn
    return $datnames
}

## OR an alternative

proc getDBs { {host "localhost"} {port "5432"} } {
    # datnames is the list to be result
    set conn [pg_connect template1 -host $host -port $port]
    set res [pg_exec $conn "SELECT datname FROM pg_database ORDER BY datname;"]

    set datnames [pg_result $res -list]
    pg_result $res -clear
    pg_disconnect $conn
    return $datnames
}

## OR an alternative

proc getDBs { {host "localhost"} {port "5432"} } {
    # datnames is the list to be result
    set conn [pg_connect template1 -host $host -port $port]
    set res [$conn exec "SELECT datname FROM pg_database ORDER BY datname;"]

    set datnames [$res -dict]
    $res -clear
    rename $conn {}
    return [dict get $datnames]
}