Explain what is meant by dirty read in the context of working with databases.

Dirty read — is a situation in database operations where one transaction reads data that has been modified by another transaction but not yet committed. If the second transaction rolls back, the first transaction has received untrustworthy information.

Example: Transaction A updates a value in a table but does not complete the operation. Transaction B reads this modified value. If Transaction A cancels the changes, the data seen by Transaction B will be false.

Dirty reads can lead to data inconsistency and application errors. To prevent this, transaction isolation levels are used, such as "Read Committed," which disallows dirty reads.