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This article will explain in detail what sort rules there are in SQLserver, and the content of the article is of high quality, so the editor will share it for you as a reference. I hope you will have a certain understanding of the relevant knowledge after reading this article.

ASCII coding

Shortly after the invention of computers, computers were only used in the United States. They created ASCII codes to represent spaces, punctuation marks, numbers, uppercase and lowercase letters, control characters, and so on. Can fully express all English. But only English is supported.

GBK coding

Later, with the popularity of computers, the Chinese people through the Chinese expansion of ASCII coding, produced the GB2312 code, which can represent more than 6000 commonly used Chinese characters. There are too many Chinese characters, including traditional Chinese characters and all kinds of characters, so there are

GBK coding, which includes the coding in GB2312, and extends a lot. China is a multi-ethnic country, almost every nation has its own independent language system, in order to express those characters, continue to expand the GBK code to GB18030 code.

Each country, like China, encodes its own language, so there are all kinds of codes, and if you don't install the corresponding codes, you won't be able to explain what the corresponding codes are trying to express.

Finally, there is an organization called ISO that can't stand it. Together, they created a code called UNICODE, which is so large that it can hold any text and logo in the world. So as long as there is a UNICODE coding system on the computer, no matter what kind of language it is in the world, when you only need to save the file, it can be interpreted normally by other computers by saving it as UNICODE code.

UTF-8 AND UTF-16

UNICODE in the network transmission, there are two standard UTF-8 and UTF-16, each transmission 8 bits (2 bytes) and 16 bits (4 bytes). As a result, some people will wonder, since UTF-8 can save so many words and symbols, why are there so many people who use codes such as GBK in China? Because UTF-8 and other codes are relatively large and take up more computer space, if most of the users are Chinese, you can also use codes such as GBK.

In general:

Unicode is a "character set"

UTF-8 is the "coding rule"

Where:

Character set: assign a unique ID (code point / code point / Code Point) encoding rule to each "character": the rule for converting a "code point" into a byte sequence (encoding / decoding can be understood as the process of encryption / decryption)

Sorting rules

For example, our commonly used: Chinese_PRC_CI_AS, the front part is the Chinese_PRC this part represents the supported Chinese mainland character set. But here is a special point to pay attention to, which is described on many blogs:

Sorting rules of Continental simplified character UNICODE

There is a lot of ambiguity here. This is not to say that this collation is Unicode for all characters. This is not accurate.

The second half of the collation is the suffix meaning:

_ BIN binary sort _ CI (CS) is case-sensitive, CI is not case-sensitive, CS (case-insensitive/case-sensitive) _ AI (AS) is case-sensitive, AI is not, AS is (accent-insensitive/accent-sensitive) _ KI (KS) is Katakana type, KI is not, KS is (kanatype-insensitive/kanatype-sensitive) _ WI (WS) whether WI is width-insensitive. WS differentiation (width-insensitive/width-sensitive)

Case sensitive: select this option if you want the comparison to treat uppercase and lowercase letters as unequal.

Distinguish stress: select this option if you want the comparison to treat accented and unstressed letters as unequal. If you select this option

The comparison also treats letters with different stresses as unequal.

Distinguish katakana: select this option if you want the comparison to treat katakana and katakana Japanese syllables as unequal.

Distinguish width: select this option if you want the comparison to treat half-width characters and full-width characters as unequal

Unicode

SQL SERVER supports Unicode. The corresponding character type is nchar,nvarchar.

About what sort of rules in SQLserver to share here, I hope the above content can be of some help to you, can learn more knowledge. If you think the article is good, you can share it for more people to see.

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