Keyword (desc)

If the hint specifies no indexes, then the optimizer considers the cost of a scan on each available index on the table and then performs the index scan with the lowest cost.

SQL ORDER BY Keyword - W3Schools Online Web Tutorials

The value specifies the degree of parallelism for the specified table. If two or more query blocks have the same name, or if the same query block is hinted twice with different names, then the optimizer ignores all the names and the hints referencing that query block. The rows of the inner table are mapped using the partitioning of the outer table. The number of servers that can be used is twice the value in the hint, if sorting or grouping operations also take place. If the statement uses an index range scan, then Oracle scans the index entries in ascending order of their indexed values. This hint does not change the default order of the index, and therefore does not specify anything more than the hint. The hint instructs the optimizer not to use one or more indexes for the specified table. As a general rule, use this distribution when the inner table size multiplied by the number of query servers is greater than the outer table size. The optimizer uses those hints when the referenced table is forced to be the inner table of a join.

The hint instructs the optimizer to place the blocks retrieved for the table at the least recently used end of the LRU list in the buffer cache when a full table scan is performed. When you specify in the surrounding query, specify it with the view name as an argument. If the statement uses an index range scan and the index is ascending, then Oracle scans the index entries in descending order of their indexed values. Oracle recommends that you use the hint, which is more versatile than the hint. The hint instructs the optimizer to optimize a statement block with a goal of best throughput-that is, minimum total resource consumption. Each parameter serves the same purpose as in "INDEX Hint". As a general rule, use this distribution when the inner table size multiplied by the number of query servers is less than the outer table size. This is the normal behavior of blocks in the buffer cache. If no subqueries are generated, then there is no transformed query, and the best plan for the untransformed query is used, regardless of the hint. In general, good software design calls for dialogs to be of this type where possible, since they do not force the user into a particular mode of operation. The NO_PARALLEL hint overrides a parameter in the DDL that created or altered the table. However, you can use the hint to specify ascending range scans explicitly should the default behavior change. As a result, direct-path can be considerably faster than conventional. The hint instructs the optimizer to check the subquery block for validity only. Party hairstyle for short hair. The DYNAMIC_SAMPLING hint instructs the optimizer how to control dynamic sampling to improve server performance by determining more accurate predicate selectivity and statistics for tables and indexes. In other words, Oracle executes the SQL statement without any attempt to replace literals with bind variables. If the hint specifies a list of available indexes, then the optimizer considers the cost of a scan on each index in the list and then performs the index scan with the lowest cost. : The optimizer ignores this hint if the inner table is not partitioned or not equijoined on the partitioning key. Usually, the optimizer considers using expansion and uses this method if it decides that the cost is lower than not using it. The simplest type of dialog box is the alert, which displays a message and may require an acknowledgment that the message has been read, usually by clicking "OK", or a decision as to whether or not an action should proceed, by clicking "OK" or "Cancel". If any parallel restrictions are violated, then the hint is ignored. The behavior of the hint depends on the specification: If the hint specifies a single available index, then the database performs a scan on this index. The hint instructs the optimizer to use a hash scan to access the specified table. This hint reduces compilation time because spreadsheet analysis can be lengthy if the number of spreadsheet rules is more than several hundreds. The NO_USE_HASH hint instructs the optimizer to exclude hash joins when joining each specified table to another row source using the specified table as the inner table. Oracle does not consider views outside of the list. NOPARALLEL_INDEX Hint The NOPARALLEL_INDEX hint has been deprecated. The concept of a document modal dialog has recently been used, most notably in OS X and Opera Browser. A type of modeless dialog box is a toolbar which is either separate from the main application, or may be detached from the main application, and items in the toolbar can be used to select certain features or functions of the application. If you use with a view list and the list contains an eligible materialized view, then Oracle uses that view regardless of its cost. Such information lets you choose an inner and outer table better than the optimizer could

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