CREATE TABLE t1 (

  a int NOT NULL PRIMARY KEY,

  b varchar(32),

  c char(16),

  d date,

  e double,

  f bit(3),

  INDEX idx1 (b, e), 

  INDEX idx2 (c, d),

  INDEX idx3 (d),

  INDEX idx4 (e, b, d)

) ENGINE= MYISAM;

INSERT INTO t1 VALUES

  (0, NULL, NULL, NULL, NULL, NULL),

  (7, 'xxxxxxxxxxxxxxxxxxxxxxxxxx', 'dddddddd', '1990-05-15', 0.1, b'100'),

  (17, 'vvvvvvvvvvvvv', 'aaaa', '1989-03-12', 0.01, b'101'),

  (1, 'vvvvvvvvvvvvv', NULL, '1989-03-12', 0.01, b'100'),

  (12, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww', 'dddddddd', '1999-07-23', 0.112, b'001'),

  (23, 'vvvvvvvvvvvvv', 'dddddddd', '1999-07-23', 0.1, b'100'),

  (8, 'vvvvvvvvvvvvv', 'aaaa', '1999-07-23', 0.1, b'100'),

  (22, 'xxxxxxxxxxxxxxxxxxxxxxxxxx', 'aaaa', '1989-03-12', 0.112, b'001'),

  (31, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww', 'aaaa', '1999-07-23', 0.01, b'001'),

  (10, NULL, 'aaaa', NULL, 0.01, b'010'),

  (5, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww', 'dddddddd', '1999-07-23', 0.1, b'100'),

  (15, 'vvvvvvvvvvvvv', 'ccccccccc', '1990-05-15', 0.1, b'010'),

  (30, NULL, 'bbbbbb', NULL, NULL, b'100'),

  (38, 'zzzzzzzzzzzzzzzzzz', 'bbbbbb', NULL, NULL, NULL),

  (18, 'zzzzzzzzzzzzzzzzzz', 'ccccccccc', '1990-05-15', 0.01, b'010'),

  (9, 'yyy', 'bbbbbb', '1998-08-28', 0.01, NULL),

  (29, 'vvvvvvvvvvvvv', 'dddddddd', '1999-07-23', 0.012, b'010'),

  (3, 'yyy', 'dddddddd',  '1990-05-15', 0.112, b'010'),

  (39, 'zzzzzzzzzzzzzzzzzz', 'bbbbbb', NULL, 0.01, b'100'),

  (14, 'xxxxxxxxxxxxxxxxxxxxxxxxxx', 'ccccccccc', '1990-05-15', 0.1, b'100'),

  (40, 'zzzzzzzzzzzzzzzzzz', 'bbbbbb', '1989-03-12', NULL, NULL),

  (44, NULL, 'aaaa', '1989-03-12', NULL, b'010'),

  (19, 'vvvvvvvvvvvvv', 'ccccccccc', '1990-05-15', 0.012, b'011'),

  (21, 'zzzzzzzzzzzzzzzzzz', 'dddddddd', '1989-03-12', 0.112, b'100'),

  (45, NULL, NULL, '1989-03-12', NULL, b'011'),

  (2, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww', 'ccccccccc', '1990-05-15', 0.1, b'001'),

  (35, 'yyy', 'aaaa', '1990-05-15', 0.05, b'011'),

  (4, 'vvvvvvvvvvvvv', 'dddddddd', '1999-07-23', 0.01, b'101'),

  (47, NULL, 'aaaa', '1990-05-15', 0.05, b'010'),

  (42, NULL, 'ccccccccc', '1989-03-12', 0.01, b'010'),

  (32, NULL, 'bbbbbb', '1990-05-15', 0.01, b'011'),

  (49, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww' , 'aaaa', '1990-05-15', NULL, NULL),

  (43, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww' , 'bbbbbb', '1990-05-15', NULL, b'100'),

  (37, 'yyy', NULL, '1989-03-12', 0.05, b'011'),

  (41, 'xxxxxxxxxxxxxxxxxxxxxxxxxx', 'ccccccccc', '1990-05-15', 0.05, NULL),

  (34, 'yyy', NULL, NULL, NULL, NULL),

  (33, 'zzzzzzzzzzzzzzzzzz', 'dddddddd', '1989-03-12', 0.05, b'011'),

  (24,  'wwwwwwwwwwwwwwwwwwwwwwwwwwww', 'dddddddd', '1990-05-15', 0.01,  b'101'),

  (11, 'yyy', 'ccccccccc', '1999-07-23', 0.1, NULL),

  (25, 'zzzzzzzzzzzzzzzzzz', 'bbb', '1989-03-12', 0.01,  b'101');

ANALYZE TABLE t1;

SELECT COUNT(DISTINCT t1.e, t1.b, t1.d) FROM t1;

DROP TABLE t1;

CREATE TABLE t2 (

  a int NOT NULL PRIMARY KEY,

  b varchar(32),

  c char(16),

  d int,

  e double,

  f bit(3),

  INDEX idx1 (b, e), 

  INDEX idx2 (c, d),

  INDEX idx3 (d),

  INDEX idx4 (e, b, d)

) ENGINE= MYISAM;

INSERT INTO t2 VALUES

  (0, NULL, NULL, NULL, NULL, NULL),

  (7, 'xxxxxxxxxxxxxxxxxxxxxxxxxx', 'dddddddd', 1990, 0.1, b'100'),

  (17, 'vvvvvvvvvvvvv', 'aaaa', 1989, 0.01, b'101'),

  (1, 'vvvvvvvvvvvvv', NULL, 1989, 0.01, b'100'),

  (12, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww', 'dddddddd', 1999, 0.112, b'001'),

  (23, 'vvvvvvvvvvvvv', 'dddddddd', 1999, 0.1, b'100'),

  (8, 'vvvvvvvvvvvvv', 'aaaa', 1999, 0.1, b'100'),

  (22, 'xxxxxxxxxxxxxxxxxxxxxxxxxx', 'aaaa', 1989, 0.112, b'001'),

  (31, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww', 'aaaa', 1997, 0.01, b'001'),

  (10, NULL, 'aaaa', NULL, 0.01, b'010'),

  (5, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww', 'dddddddd', 1999, 0.1, b'100'),

  (15, 'vvvvvvvvvvvvv', 'ccccccccc', 1990, 0.1, b'010'),

  (30, NULL, 'bbbbbb', NULL, NULL, b'100'),

  (38, 'zzzzzzzzzzzzzzzzzz', 'bbbbbb', NULL, NULL, NULL),

  (18, 'zzzzzzzzzzzzzzzzzz', 'ccccccccc', 1990, 0.01, b'010'),

  (9, 'yyy', 'bbbbbb', 1998, 0.01, NULL),

  (29, 'vvvvvvvvvvvvv', 'dddddddd', 1999, 0.012, b'010'),

  (3, 'yyy', 'dddddddd',  1990, 0.112, b'010'),

  (39, 'zzzzzzzzzzzzzzzzzz', 'bbbbbb', NULL, 0.01, b'100'),

  (14, 'xxxxxxxxxxxxxxxxxxxxxxxxxx', 'ccccccccc', 1990, 0.1, b'100'),

  (40, 'zzzzzzzzzzzzzzzzzz', 'bbbbbb', 1989, NULL, NULL),

  (44, NULL, 'aaaa', 1989, NULL, b'010'),

  (19, 'vvvvvvvvvvvvv', 'ccccccccc', 1990, 0.012, b'011'),

  (21, 'zzzzzzzzzzzzzzzzzz', 'dddddddd', 1989, 0.112, b'100'),

  (45, NULL, NULL, 1989, NULL, b'011'),

  (2, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww', 'ccccccccc', 1990, 0.1, b'001'),

  (35, 'yyy', 'aaaa', 1990, 0.05, b'011'),

  (4, 'vvvvvvvvvvvvv', 'dddddddd', 1999, 0.01, b'101'),

  (47, NULL, 'aaaa', 1990, 0.05, b'010'),

  (42, NULL, 'ccccccccc', 1989, 0.01, b'010'),

  (32, NULL, 'bbbbbb', 1990, 0.01, b'011'),

  (49, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww' , 'aaaa', 1990, NULL, NULL),

  (43, 'wwwwwwwwwwwwwwwwwwwwwwwwwwww' , 'bbbbbb', 1990, NULL, b'100'),

  (37, 'yyy', NULL, 1989, 0.05, b'011'),

  (41, 'xxxxxxxxxxxxxxxxxxxxxxxxxx', 'ccccccccc', 1990, 0.05, NULL),

  (34, 'yyy', NULL, NULL, NULL, NULL),

  (33, 'zzzzzzzzzzzzzzzzzz', 'dddddddd', 1989, 0.05, b'011'),

  (24,  'wwwwwwwwwwwwwwwwwwwwwwwwwwww', 'dddddddd', 1990, 0.01,  b'101'),

  (11, 'yyy', 'ccccccccc', 1999, 0.1, NULL),

  (25, 'zzzzzzzzzzzzzzzzzz', 'bbb', 1989, 0.01,  b'101');

ANALYZE TABLE t2;

SELECT COUNT(DISTINCT t2.e, t2.b, t2.d) FROM t2;