What is the difference between clustered and non-clustered indexes in MySQL?

There are differences between clustered indexes and non-clustered indexes in MySQL.

1. Data storage method: Clustered index defines the physical storage order of data in a table, where rows in the table are stored in the order of the clustered index. Non-clustered indexes, on the other hand, are just pointers to data rows and do not affect the actual storage location of data on disk.
2. Uniqueness: There can only be one clustered index in a table because it determines the storage order of data. However, a table can have multiple non-clustered indexes.
3. Performance query: Clustered indexes perform better for range queries and sorting operations because related data rows are physically stored together. Non-clustered indexes require additional IO operations to retrieve related data rows for range queries and sorting operations.
4. Performance on updates: Clustered indexes may have poorer performance for insertions, deletions, and updates as they require reorganizing the physical storage order of data. Non-clustered indexes, on the other hand, have better update performance as they only require updating the index.
5. Index size: Clustered indexes are typically larger than non-clustered indexes because they contain the actual data. Non-clustered indexes only include the values of the indexed columns and pointers to the actual data rows.

It is necessary to choose the appropriate index type based on specific scenarios and requirements.