postgres=# select 'aa' = any(string_to_array('aa,bb,cc,dd',','));
 ?column? 
----------
 t
(1 row)

postgres=# select 'bb' = any(string_to_array('aa,bb,cc,dd',','));
 ?column? 
----------
 t
(1 row)

postgres=# select 'cc' = any(string_to_array('aa,bb,cc,dd',','));
 ?column? 
----------
 t
(1 row)

postgres=# select 'abc' = any(string_to_array('aa,bb,cc,dd',','));
 ?column? 
----------
 f
(1 row)

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