What are the effects of using NOLOCK in SQL Server queries?

Data and Databases
1

Could anyone clarify the effects of using the SQL Server NOLOCK hint in database queries? When is it beneficial versus risky? For example, in a high-traffic financial application, under which circumstances is this approach acceptable? Consider this code sample:

SELECT Total, Date FROM Sales WITH (READUNCOMMITTED);

Any insights on when to use or avoid such hints would be appreciated.

2

hey im curisus if nolock really speeds up reads in high taffic systems even if it might return dodgy data sometimes. has anyone seen it work well without issues? i’d love to hear more real-world experinse on balancing risk and speed.