Shulou(Shulou.com)05/31 Report--

Today, I will talk to you about the difference between fixed-length char (n) and variable-length varchar (n) in SQL Server. Many people may not know much about it. In order to make you understand better, the editor has summarized the following content for you. I hope you can get something according to this article.

Char (n) is a fixed-length format, and the field in the format char (n) occupies a fixed width of n characters. If the actual data length exceeds n, the extra part will be intercepted, and if the length is less than n, it will be filled with empty characters.

Varchar (n) is a variable-length format in which fields allocate space according to the actual data length without wasting space, but the speed of searching the data is a little more troublesome.

Generally speaking, as long as a table has a field defined as type varchar (n), the rest of the fields defined with char (n) are actually of type varchar (n).

If your length itself is not long, such as 3 to 10 characters, then using the char (n) format is more efficient and faster to search. But if some data is very long, some data is relatively short, such as the profile of registered users, there is really no way, and care about wasted space, then use the varchar (n) format.

After reading the above, do you have any further understanding of the difference between fixed-length char (n) and variable-length varchar (n) in SQL Server? If you want to know more knowledge or related content, please follow the industry information channel, thank you for your support.

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