Add unique index. SQLite3

sql sqlite ddl unique-index
I159 picture I159 · Oct 20, 2011 · Viewed 22.4k times · Source

I need to add a unique field index to an existing table. I made this row:

ALTER TABLE auth_user ADD UNIQUE INDEX (email);

The table and the field are already exist. The error is:

Query Error: near "UNIQUE": syntax error Unable to execute statement

What am I missed? Did it have any specific requirements for SQLite3?

Answer

Adriano Carneiro picture Adriano Carneiro · Oct 20, 2011 
CREATE UNIQUE INDEX IF NOT EXISTS MyUniqueIndexName ON auth_user (email)

Also, read the official manual:

http://www.sqlite.org/lang_createindex.html

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