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setting a collumn to be unique in existing table

hi all

ive been looking on the mysql site but i cant find the syntax to set a
collumn in an existing table to be unique.

could someone please give an example of how to do this.

i believe it goes something like: alter table tblname add unique
colname

but i could be wrong

Oct 22 '06 #1
2 2421
also the syntax to unset this would also be useful. thanks

Oct 22 '06 #2

mc******@googlemail.com wrote:
also the syntax to unset this would also be useful. thanks
ALTER TABLE `my_table` ADD UNIQUE (`my_field`)

ALTER TABLE `my_table` DROP INDEX `my_field_index`

have a look at phpmyadmin

Oct 22 '06 #3

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