how to update only one field in 1 table?

[viccop]

i want to make one update button, which will help me update data at one any field by add (or deduct, multiplied, divided) with old data exist in that field in table. it means, example as old data in that field is 20, when i input new data is 10 to update in the field, then data in that field will be 30 (=20+10, it means, = old data+update data and etc -, x, :,...). please help me!


Thanks in advance,

[viccop]

please help me! i don't know about it i had finded in google, and seem it is "insert query" kind, but i don't know how to do...

[ibgreat]

Are you using a bound or unbound form?

You need a seperate data entry field if it is a bound form. This is because as soon as you change the data it will be changed in the underlying table.

[viccop]

this is the second question i want to know. pls help me! i want to create a button in form, it will be used to when i click that button, it will go to a text box and display as on enter (or klick) into that text box (the command will active with select all text mode in text box)?