mysql - Is it good to use a default of NULL? -

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i have columns may contain data if user wants provide it.

example | email | first name | last name |

email - required column set not null - default: none

first name - not required column set null - default: null

last name - not required column set null - default: null

in phpmyadmin when creating/editing column; has option saying default: drop down showing none | defined | null | current timestamp

because first name | last name optional , not required should choose default null or maybe none?

which best , why please?

i know there many discussions on not find answered question; more in regards allowing null or not null, question default value.

you should set them default:null if user doesn't provide info fields, should null obviously.


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