January 2018
Intermediate to advanced
446 pages
12h 57m
English
Content preview from MySQL 8 Cookbook
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UNIQUE index
If you want the index to be unique, you can specify the keyword UNIQUE. For example:
mysql> ALTER TABLE employees ADD UNIQUE INDEX unique_name (last_name, first_name);# There are few duplicate entries in employees database, the above statement is shown for illustration purpose only.