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This article mainly introduces "what kinds of symbols are not equal to mysql". In daily operation, I believe that many people have doubts about what kinds of symbols are not equal to symbols in mysql. The editor consulted all kinds of materials and sorted out simple and easy-to-use methods of operation. I hope it will be helpful for everyone to answer the doubts that "symbols are not equal to symbols in mysql". Next, please follow the editor to study!

There are two kinds of unequal symbols in mysql: "! =" and ""; they can be used to determine whether numbers, strings, and expressions are not equal. For "! =" and "", if the operands on both sides are not equal, the return value is 1, otherwise the return value is 0; if one of the operands on both sides is NULL, the return value is also NULL.

The operating environment of this tutorial: windows7 system, mysql8 version, Dell G3 computer.

In mysql, there are two kinds of symbols that do not mean:

! =

The unequal operator (or! =) can be used to determine whether numbers, strings, or expressions are not equal. If the operands on both sides are not equal, the return value is 1, otherwise the return value is 0; if one of the operands on both sides is NULL, then the return value is also NULL.

Example: use and! = to make unequal judgments

Mysql > SELECT 'goodwill gift godsend NULLNULL 12, 4, 4, 5, 5, (1: 3)! = (2: 1), +-+-+ | 'good''god' | 12 | 4-4 | 5-5 | (1-3)! = (2-1) | NULLNULL | +-+- +-+ | 1 | 1 | 0 | 1 | 1 | NULL | +- -+-+ 1 row in set (0.00 sec)

As can be seen from the results, the two operators that are not equal to the same function can be compared and judged by numbers, strings, and expressions.

At this point, the study of "what are the symbols in mysql is not equal to which are there" is over. I hope I can solve your doubts. The collocation of theory and practice can better help you learn, go and try it! If you want to continue to learn more related knowledge, please continue to follow the website, the editor will continue to work hard to bring you more practical articles!

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