Index in the database

 Index

Large books have indexes or indexes at the end to facilitate the search for various topics. Through it, it is known that a topic has been discussed on some page of that book. In the case of database also there is system of such index to find various data quickly. Such indexes increase the performance of searching for any information in the database. Simply put, an index is a pointer to data in a table. The created index is stored in a different location from that table. The main purpose of the index is to speed up data retrieval from the database. Indexes can be created or deleted without changing the data. However, queries may take longer if an index is deleted. Keep in mind that indexes occupy physical space and in some cases may be larger than the original data table. Databases need to create indexes to increase query performance. Indexes can be created during table creation or later. The create index statement creates an index for a column in a table. However, it should be remembered that the name and syntax of this command may be different depending on the database system. However, most relational database systems use the create index statement to create indexes. Its syntax is as follows:

Create index index_name on table_name