PRIMARY vs INDEX keys

[zzz]

2 questions:

1.=================
I've installed a newer version of PHPMyAdmin adn noticed a message on one of my tables saying:

PRIMARY and INDEX keys should not both be set for column ID

I am also presented with an option to delete either PRIMARY or INDEX key. The ID fields must be a unique value and also has auto_increment setting.

I am not sure which key I must delete and which one to keep.

2. ================

The new PHPMyAdmin now shows OVERHEAD and some of my tables have it. What is it and if it's not good, how do I resolve it?

[laserlight]

Remove the extra index. I believe the primary key is indexed and it certainly is unique, and I guess you already have it as auto incremented.