Synonyms and Indexes

Some of the essential properties of indexes are:

• An Index is a schema Object
• Indexes can be formed explicitly or automatically
• Indexes are mainly used to speed up the retrieval of rows
• Indexes are physically and logically independent of the table. It means they can be formed or dropped at any time and have no cause on the base tables or other indexes.
• Though, when a table is dropped corresponding indexes are also dropped.