Today design table structure, add a few fields, the results of the error
The situation was that there would have been 50 fields in the table, and this time the need to add 18 fields, I set all 18 fields to Vachar 255. The result was an error. I don't understand why.
This mistake with Baidu translated out is "the line is too big." The largest line in the scale. Except blobs,65535. ”
What the hell is going on here? Is there a limit to a single record?
The length of the 18 fields was set to 100 and the creation was successful.
See the following text on the Internet
Log length for MySQL
MySQL defaults to a record with a maximum length of 65535 bytes, with all fields added together, the number of bytes cannot exceed 65535. However, the length of a field in MySQL uses bytes to specify int, and some field types are specified using the number of characters.
What is the 1 characters? Depending on the character encoding,
The latin1 character set is 1 characters and occupies 1 bytes.
GBK Character Set 1 characters occupy 2 bytes
UTF8 Character set 1 characters occupy 3 bytes
You also need to consider the record length of varchar, which needs to be recorded using 1 or 2 bytes.
You also need to consider the issue of null values.
MySQL single record length Max 65535