Problem with create unique index

[Miguel Oliveira]

Hello, 

I'm trying to create an unique index like this (to avoid login duplicates):

CREATE UNIQUE INDEX alias_index ON users(alias)

I always get this answer from mysql:

Couldn't  create  the  alias  index on the users table!  (Column 'alias' is
used with UNIQUE or INDEX but is not defined as NOT NULL)

I've this working in an older version of mysql.  At home i'm using 3.22.19b
and gives me that error.



regards,
Miguel Oliveira

E-mail: mailto:miguel@stripped
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