Field and all records change same time

[DaRTHY]

Hello Friends

I need to change my all field information at the same time. For example :

FIELD
a
a
a
a
a
a

This is my field and i want to change there b instead of a (of course there is 5000 records)
Is that possible ? how can i do that ? or can i change at the same time 1by1 its not an option.:banghead:

Ty for helps

 

[namliam]

A simple update query would do that trick, however having even things like this is a big sign of bad design

 

[DaRTHY]

i did not create this database but i must find the solution.
How simple is that. I do not have and find any solution.
----o-----
If i fix it i ll 1 more problem. They want to from me 10-5 = ? the problem is
these numbers are not integer instead of String.
still can i substruction this 2 numbers ??