Slight comparison of char and varchar in MySQL

Slight comparison of char and varchar in MySQL

In the MySQL database (other databases should be similar), and the two types can be set to the maximum degree when designing the database, one of their differences is that "the content stored as char is always stored as a string of the specified length (if each input length reaches, it is supplemented with spaces, the varchar string is stored as its actual string length,

1. varchar columns tend to occupy less disk space.

2. The access speed of varchar is faster than that of char only when InnoDB table type is used. In other cases, the access speed of char is greater than that of varchar.

3. When retrieving data, MySQL will delete extra spaces (that is, adding length) in the char-type data column. For varchar, this operation is performed when data is inserted.

4. in MySQL, char (length) occupies length bytes, while varchar (length) occupies Length + 1 byte.