Let's suppose I have my table named "say2" like the above.Code:

say2

(n) title

(1) Mom

(2) WTD

(3) SUN

(4) Earth

(5) Asia

(6) Europe

(7) Venus

(8) Korea

The code1 below produces the result1 below.

And the code2 below produces the result2 below.Code:

code1

SELECT n, title

FROM say2

WHERE n=1 or n =3 or n =5

result1

(1) Mom

(3) SUN

(5) Asia

Let's UNION them like the belowCode:

code2

SELECT n, title

FROM say2

WHERE n=5 or n =7 or n =8

result2

(5) Asia

(7) Venus

(8) Korea

code3and itsresult3.

Now I think It would be better if there is the opposite of UNION in mySQL.Code:

code3

SELECT n, title

FROM say2

WHERE n=1 or n =3 or n =5

UNION

SELECT n, title

FROM say2

WHERE n=5 or n =7 or n =8

result3

(1) Mom

(3) SUN

(5) Asia

(7) Venus

(8) Korea

UNION means result1 + result2.

I mean that the opposite of UNION means result1 - result2.

The following would-be code4 doesn't work correctly, but I hope it shows what I want.

Code:

would-be code4

SELECT n, title

FROM say2

WHERE n=1 or n =3 or n =5

the opposite of UNION

SELECT n, title

FROM say2

WHERE n=5

target result4

(1) Mom

(3) SUN

or

would-be code5

SELECT n, title

FROM say2

WHERE n=1 or n =3 or n =5

the opposite of UNION

SELECT n, title

FROM say2

WHERE n=5 or n =7 or n =8

target result5

(1) Mom

(3) SUN