Accessing and Changing Relational Data
Hints
This table lists the options available for join hints, query hints, and table hints in Microsoft® SQL Server™ 2000.
Hint type | Option | Description |
Default setting |
---|---|---|---|
Join | LOOP | HASH | MERGE | REMOTE |
Specifies the strategy to use when joining the rows of two tables. | Chosen by SQL Server. |
Query | { HASH | ORDER } GROUP | Specifies whether hashing or ordering is used to compute GROUP BY and COMPUTE aggregations. | Chosen by SQL Server. |
Query | { MERGE | HASH | CONCAT } UNION |
Specifies the strategy to use for all UNION operations within the query. | Chosen by SQL Server. |
Query | FAST integer | Optimizes the query for retrieval of the specified number of rows. | No such optimization. |
Query | FORCE ORDER | Performs joins in the order in which the tables appear in the query. | Chosen by SQL Server. |
Query | ROBUST PLAN | Creates a plan that accommodates maximum potential row size. | Chosen by SQL Server. |
Table | FASTFIRSTROW | Has the same effect as specifying the FAST 1 query hint. | No such optimization. |
Table | INDEX = | Instructs SQL Server to use the specified indexes for a table. | Chosen by SQL Server. |
Table | HOLDLOCK | SERIALIZABLE | REPEATABLEREAD | READCOMMITTED | READUNCOMMITTED | NOLOCK |
Specifies the isolation level for a table. | Defaults to a transaction isolation level. |
Table | ROWLOCK | PAGLOCK | TABLOCK | TABLOCKX | NOLOCK |
Specifies locking granularity for a table. | Chosen by SQL Server. |
Table | READPAST | Skips locked rows altogether. | Wait for locked rows. |
Table | UPDLOCK | Takes update locks instead of shared locks. Cannot be used with NOLOCK or XLOCK. | Take shared locks. |
Table | XLOCK | Takes an exclusive lock that will be held until the end of the transaction. Cannot be used with NOLOCK or UPDLOCK. | Chosen by SQL Server. |