linux set environment variable from command line code example

Example 1: shell set environment variable

export VARNAME="my value"      # shorter, less portable version

Example 2: how to create env variable from cmd

set varname
set varname=value
set varname=
set

Example 3: linux set environment

# syntax 
# setenv SHELL *

# example
setenv SHELL /usr/bin/bash

Example 4: linux set environment variable

# Linux - Bash 

# syntax 
# export *=*;

# example 
export ORACLE_SID='sales_database';