CREATE INDEX

An index is a database object that helps to improve the performance of queries by allowing for faster retrieval of data. Indexes are created on columns in a table to speed up the process of searching for records based on those columns.

To create an index in a database, you can use the following SQL syntax:

CREATE INDEX index_name
ON table_name (column_name);

In this syntax:

• index_name is the name of the index that you want to create.
• table_name is the name of the table on which you want to create the index.
• column_name is the name of the column on which you want to create the index.

For example, if you have a table called employees and you want to create an index on the last_name column, you can use the following SQL statement:

CREATE INDEX idx_last_name
ON employees (last_name);

This will create an index called idx_last_name on the last_name column of the employees table. This index will help to speed up queries that involve searching for records based on the last_name column.