MySQL String Split to Array

SELECT SUBSTRING_INDEX(
  SUBSTRING_INDEX('foo#bar#baz#qux', '#', 2), '#', -1
);

+----------------------------------------------------------------------+
| SUBSTRING_INDEX(SUBSTRING_INDEX('foo#bar#baz#qux', '#', 2), '#', -1) |
+----------------------------------------------------------------------+
| bar                                                                  |
+----------------------------------------------------------------------+
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