Indexescreated

Indexescreated is a term that refers to the act or process of creating indexes within a database system. Indexes are specialized data structures that improve the speed of data retrieval operations on a database table. Think of them like the index in the back of a book; they allow the database to quickly locate specific rows without having to scan the entire table.

When a database administrator or developer creates an index on one or more columns of a table, they are essentially building a lookup table. This lookup table stores a sorted copy of the indexed column values and pointers to the corresponding rows in the actual table. Queries that filter or sort based on these indexed columns can then use the index to find the relevant data much faster than a full table scan.

The creation of indexes involves trade-offs. While they significantly speed up read operations (SELECT statements), they can slow down write operations (INSERT, UPDATE, DELETE statements) because the index itself needs to be updated along with the table data. Therefore, careful consideration is given to which columns should be indexed, balancing the need for faster retrieval against the overhead of maintaining the index. The decision to create an index is often based on query patterns and performance analysis.