indexing - How to/ Where to delete/edit an index from MySql which prevents duplicates row -

i'm using sugarcrm , few weeks ago executed a query on mysql created index prevent duplicate rows. can see or find , edit or delete ? i'm not able remember exact query it's needed add more columns. using mysql few weeks.

mysql error 1062: duplicate entry 'example-dyplicate' key 'idx_name'

to see structure of table, including indexes, use:

show create table tablename; 

you can delete index with:

drop index indexname on tablename; 

there's no way edit index. if want change index, drop , add new index new columns want. however, can both in single query using alter table:

alter table tablename drop index indexname add index indexname (col1, col2, ...);