In which scenarios can indexes be used in MySQL?

There are various scenarios where indexes are utilized in MySQL.

1. Speed up searching: Creating an index for a column that is frequently used for search operations can help accelerate the search speed.
2. Quick sort: when a column is frequently used for sorting operations, creating an index for that column can speed up the sorting process.
3. Speed up connections: Indexing the columns used for joining multiple tables can help to accelerate the connection speed.
4. Unique constraint: A unique index can be created for a column to ensure that the values in that column are unique.
5. Primary key constraint: a primary key index can be created for a column to improve the performance of primary key queries.
6. Grouping and aggregating: When using GROUP BY and aggregate functions for grouping and aggregating operations, creating indexes on relevant columns can speed up query performance.
7. Range query: Creating an index for the corresponding column can speed up the query when using range queries such as BETWEEN, IN, LIKE, etc.
8. Constraint check: an index can be created on a column to ensure that the values in that column meet a certain constraint.
9. Random Access: In order to improve access speed when needing to access a particular part of a table randomly, you can create an index for the relevant columns.
10. Reducing IO operations: Indexes can decrease disk IO operations and improve database performance.