Oracle 23c

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CREATE FUNCTION number_of_set_bits(
  i NUMBER
) RETURN NUMBER DETERMINISTIC
IS
  v NUMBER := i;
  c_max CONSTANT NUMBER := POWER(2, 32);
BEGIN
  v := v - BITAND(TRUNC(v/2), TO_NUMBER('55555555', 'XXXXXXXX'));
  v := MOD(
         BITAND(v, TO_NUMBER('33333333', 'XXXXXXXX'))
         + BITAND(TRUNC(v/4), TO_NUMBER('33333333', 'XXXXXXXX')),
         c_max
       );
  v := BITAND(v + FLOOR(v/16), TO_NUMBER('0F0F0F0F', 'XXXXXXXX'));
  RETURN TRUNC(MOD(v * TO_NUMBER('01010101', 'XXXXXXXX'), c_max) / POWER(2, 24));
END;
/
SELECT testbitmap AS original_bitmap,
       NUMBER_OF_SET_BITS(testbitmap)
FROM   (
  SELECT BIN_TO_NUM(1,1,0,0,1,1,0,0,0,1,1,0,1,0,1,1,1,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0)
           AS testbitmap
  FROM   DUAL
)


ORIGINAL_BITMAP
NUMBER_OF_SET_BITS(TESTBITMAP)


3429605376
11


CREATE OR REPLACE FUNCTION number_of_set_bits(i NUMBER) RETURN NUMBER DETERMINISTIC
  AS LANGUAGE JAVA NAME 'java.lang.Long.bitCount( long ) return long';
/
SELECT testbitmap AS original_bitmap,
       NUMBER_OF_SET_BITS(testbitmap)
FROM   (
  SELECT BIN_TO_NUM(1,1,0,0,1,1,0,0,0,1,1,0,1,0,1,1,1,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0)
           AS testbitmap
  FROM   DUAL
)


ORIGINAL_BITMAP
NUMBER_OF_SET_BITS(TESTBITMAP)


3429605376
11