Change the url of a WordPress in bash

change_wp_url.sh

function chWpUrl()
{
    db=$1
    from=$2
    to=$3
    request="UPDATE wp_options SET option_value = REPLACE(option_value, '$from', '$to'); 
    UPDATE wp_posts SET guid = REPLACE(guid, '$from', '$to'); 
    UPDATE wp_posts SET post_content = REPLACE(post_content, '$from', '$to');
    UPDATE wp_comments SET comment_author_url = REPLACE(comment_author_url, '$from', '$to'),
                           comment_content = REPLACE(comment_content, '$from', '$to')
                           WHERE comment_type <> '';"
   
   if [[ $4 == 'get' ]]; then
       echo $request
   else
       (echo $request) | mysql $db
   fi
}