Same as the read uncommitted isolation level. Request no shared locks for the hinted tables thus allowing dirty reads. Additionally it allows allocation order scans (reads in physical order instead of index order) which cause nolock's other data anomalies, the missing rows and duplicate rows.
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability
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