If I leave length/values field of integer type blank in MySQL how much length of data can it store?

Question

When creating a table we normally make id field of integer type. But if I don't specify any value in length field how much length data will it store?

Solution 1

Juhana thanks for your link and answer. I got it. Length is for displaying how many characters will be shown and not how much data can be stored. So if I say integer type length is 3 then id will display upto 999 but will store values beyond that. I hope I got it right.

Solution 2

I found an explanation elsewhere that says the value/length you specify when creating a numeric column only comes into play if you are using zerofill queries. Example here.

If you stored a value of 5
INT(4) would display 0005
INT(11) would display 00000000005

There's a note in mysql docs that tells of possible trouble when making it too small, so personally I just leave it blank when making a new numeric column.

Comments

[JJJ]

Well, not exactly. See the quote in the duplicate: "The display width does not constrain the range of values that can be stored in the column. Nor does it prevent values wider than the column display width from being displayed correctly." If you have values >999 in a field with length 3, the values are shown correctly but the layout might break. It's basically just for making sure columns line up nicely when showing the table data.