How to concatenate multiple strings together with a given separator using the CONCAT_WS() function?

CONCAT_WS(separator, string1, string2, ...) is a MySQL built-in function that concatenates multiple strings together. For example:

SET @host = 'dba';
SET @domain = 'FYIcenter';
SET @tld = 'com';

SELECT CONCAT_WS('.', @host, @domain, @tld);
  -- +--------------------------------------+
  -- | CONCAT_WS('.', @host, @domain, @tld) |
  -- +--------------------------------------+
  -- | dba.FYIcenter.com                    |
  -- +--------------------------------------+

Reference information of the CONCAT_WS() function:

CONCAT_WS(separator, str1, str2, ...): str
  Returns the string that results from concatenating the arguments except
  for the first one, which is used as concatenation separator, like the
  CONCAT() function. If the separator is NULL, the result is NULL.

Arguments, return value and availability:
  separator: Required. The given separator.
  str1: Required. The first given string to concatenate for.
  str2: Optional. The second given string to concatenate for.
  str: Return value. The string of concatenation of all given strings.
  Available since MySQL 4.0.

Related MySQL functions:

• CONCAT() - Concatenating Strings

⇒ CONV() - Binary/HEX String and Integer Conversion

⇐ CONCAT() - Concatenating Strings

⇑ MySQL Functions on Character String Values

⇑⇑ MySQL Function References