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Other Memory Management Topics in .NET Integrated ean13+5 in .NET Other Memory Management Topics

20. using barcode integrated for vs .net control to generate, create upc-13 image in vs .net applications. QR Code Spevcification Current Unique Sets Se .NET European Article Number 13 ts Found Find/Created Executions Find/Exec sets SQL Created /1000 PCT /1000 PCT ------- ------ ------- ------------ ------------ ----------- --------1,512 2 9,503 24 255.26 300 8.

09. A Find/Create ratio le ss than 100 percent means that most cached result sets are not used even once and might suggest a review of the use of the RESULT_CACHE hint or overall result set cache configuration. However, it could be that while most result sets are not efficient, a few are extremely efficient and more than make up for those that get flushed out unused. We can examine the efficiency of individual result sets by looking at statistics for SQLs in the cache that include the RESULT CACHE operation in their plan.

The following query does that: SQL> WITH result_cache AS (SELECT cache_id,. 2 3 4 5 6 7 8 9 10 11 Visual Studio .NET GS1-13 12 13 14 15 16 17 18 19 20 21 22 23 24 COUNT( * ) cached_result_sets, SUM(scan_count) hits FROM v$result_cache_objects GROUP BY cache_id) SELECT /*+ ordered */ s.sql_id, s.

executions, o.cached_result_sets, o.hits cache_hits, ROUND(s.

rows_processed / executions) avg_rows, buffer_gets, ROUND(buffer_gets / (executions - o.hits)) avg_gets_nocache, round((buffer_gets / (executions - o.hits)) *o.

hits) estd_saved_gets, s.sql_text FROM v$sql_plan p JOIN result_cache o ON (p.object_name = o.

cache_id) JOIN v$sql s ON (s.sql_id = p.sql_id AND s.

child_number = p.child_number) WHERE operation = RESULT CACHE order by 7 desc ;. Other Memory Management Topics Estd. Saved Cached Cac .net framework GTIN-13 he Buffer Avg Gets Buffer gets Execs Results Hits Gets w/o Cache /1000 -------- ------- ----------- --------------- ---------- -------------Sql Text ---------------------------------------------------------------------4,388 494 3,894 150,279 304 1,184,588 SELECT /*+ RESULT_CACHE */ PROD_NAME, SUM(AMOUNT_SOLD) FROM SALES JOIN PRODUCTS USING (PROD_ID) JOIN CUSTOMERS USING (CUST_ID) WHERE CUST_ID = :B2 AND TIME_ID > :B1 GROUP BY PROD_NAME 14,187 3,128 11,059 9,389 3 33,195 SELECT /*+ RESULT_CACHE */ SUM(AMOUNT_SOLD) FROM SALES_ARCHIVE JOIN PR ODUCTS USING (PROD_ID) JOIN CUSTOMERS USING (CUST_ID) WHERE PROD_ID = :B2 AND CUST_ID = :B1.

Note that both of the preceding SQL statements generated more than one cached result set. Indeed 494 and 3,128 cached result sets were created for the two SQLs. The result set cache can create a unique cached result set for each distinct combination of bind variables provided for each statement.

For suitable SQL statements, substantial savings in overhead can be achieved. The two statements illustrated showed reductions in overhead of between 80 percent and 90 percent. Not all the result sets will be reused, and some might have been flushed out of memory before being reused.

Nevertheless, we can see that for the two preceding statements, cache hits were a significant majority of the overall execution count.. The result cache can b Visual Studio .NET EAN13 e effective for expensive queries on relatively static tables that return small result sets. RESULT CACHE DEPENDENCIES Cached result sets will be eliminated from cache when DML alters any of the dependent tables involved in the query.

You can list the queries in the cache and the dependent objects by using the following query:. SQL> SELECT /*+ ord ered */ max(co.name) cached_object, 2 count(*) result_sets_cached, do.cache_id dependency 3 FROM v$result_cache_dependency d 4 JOIN 5 v$result_cache_objects do 6 ON (d.

depend_id = do.id) 7 JOIN. 8 9 10 11 v$result_cac GTIN-13 for .NET he_objects co ON (d.result_id = co.

id) group by do.cache_id, co.cache_id order by cached_object;.

20 . No of CACHED_OBJECT Re VS .NET EAN13 sult Sets ---------------------------------------- ----------SELECT /*+ RESULT_CACHE */ PROD_NAME, SU 194 M(AMOUNT_SOLD) FROM SALES JOIN PRODUCTS USING (PROD_ID) JOIN CUSTOMERS USING (CU ST_ID) W. Dependent Object -----------------OPSG.CUSTOMERS OPSG.SALES OPSG.PRODUC EAN/UCC-13 for .

NET TS SELECT /*+ RESULT_CACHE */ SUM(AMOUNT_SO LD) FROM SALES_ARCHIVE JOIN PRODUCTS USING (PROD_ID) JOIN CUSTOMERS USING (CUST_ ID) WHER 1,319 OPSG.PRODUCTS. OPSG.SALES_ARCHIVE OPSG.CUSTOMERS RESULT CACHE LATCHES T VS .NET ean13+5 he Result Cache: RC Latch (Oracle 11g Release 2) or the Result Cache: Latch (Oracle 11g Release 1) controls the creation and deletion of result sets in the Result set cache. Contention for this latch occurs if multiple sessions attempt to simultaneously create cached result sets.

This sort of contention will not normally occur if long-running expensive queries are cached because the rate at which new entries are loaded will be low. However, if you attempt to cache all SQLs, or those that run at high frequencies, this latch contention might dominate response time. The Result Cache latch does not have its own wait event.

Contention for the latch shows up under the general purpose latch free wait event:. SQL> select * from latch_delta_view; WAIT_TYPE TOTAL_WAITS TIME_WAITED_MS PCT_TIME SAMPLE_SEC -------------------- ----------- -------------- ---------- ---------CPU 97098.449 91.7 31 latch free 365 3403.

802 3.21 31 latch: cache buffers 35 1822.472 1.

72 31 chains User I/O 40 1455.908 1.37 31 latch: row cache 16 1133.

492 1.07 31 objects.
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