SQL DB what to set the maximum length?

Question

PHP

I'm starting to design a database .
I need to make several varchar fields
. And I stopped at the question, what is the maximum length of the fields to set?
50?100?250 characters?
again, I can't know right now how long my title or name can be
. How to determine what max length to set?
If you set 99999 what will happen then? Will the base weigh more?

Answer 1

не мешало бы увидеть текст ошибки, по коду первое что бросается в галаза:
1. Зачем Вы взяли переменые $platform, $appName, $store_url, $status в `` это же значеня полей...
2. Перед WHERE не должно быть запятой

Answer 2

At the design stage, you can’t guess exactly how much this or that parameter will take. You can only guess, for example:
Surname - it is unlikely that the length of a person's last name is more than 30 characters First
Name - it is unlikely that the length of a person's first name is more than 20 characters.
Based on such an analysis, make an approximate length, and during operation, already with the help of logging and a validation system, see what and how.

Answer 3

stackoverflow.com/questions/332798/equivalent-of-v... You can read the manual about RTFM
limitations .