MySQL series: (4) Details

The varchar type of the MySQL database is in versions below 4.1, nvarchar (characters that store Unicode data types), whether a character or a Chinese character, are stored as 2 bytes, which is generally used as input in Chinese or other languages, which is not easily garbled; varchar: The kanji is 2 bytes, the other character designators is 1 bytes, and varchar is suitable for inputting English and numerals.

4.0 versions, varchar (20), refers to 20 bytes, if stored UTF8 kanji, can only save 6 (each Kanji 3 bytes), 5.0 version above, varchar (20), refers to 20 characters, regardless of the number of storage, Letters or UTF8 Kanji (3 bytes per kanji), can be stored 20, the maximum size is 65532 bytes, varchar (20) in MYSQL4 is the largest is only 20 bytes, but MYSQL5 according to the code, the storage size is different

MySQL series: (4) Details