Question

INT(1) – I know, 1 does not mean 1 digit, it represents client output display format only.

but what does this signify

i have declared YEAR as int(1), I still see all 4 bytes. please tell me what does INT(1) means ?

SELECT * FROM TEST_USERDB;

+----+--------+------+
| ID | NAME   | YEAR |
+----+--------+------+
|  1 | abcccc | 2012 |
|  2 | stack  |   99 |
+----+--------+------+

Answer 1

An unsigned int has the max value of 4294967295 no matter if its
INT(1) or int(10) and will use 4 bytes of data.

So, what does the number in the brackets mean? It pretty much comes
down to display, its called the display-width. The display width is a
number from 1 to 255. You can set the display width if you want all of
your integer values to “appear”. If you enable zerofill on the row,
the field will have a default value of 0 for int(1) and 0000000000 for
int(10).

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