the concept “transaction“ of DBMS and the explain the five states of a transaction.,程序员大本营,技术文章内容聚合第一站。
Figure 4: Execution plan accessing the SQL cursor cache, using the basic format The arguments accepted by DBMS_XPLAN.DISPLAY_CURSOR are: SQL ID (default null, means the last SQL statement executed in this session), child number (default 0), format, controls the amount of ...
3 EXPLAIN PLAN 当某个性能SQL死掉,不出结果时,我们可以用这个,这个肯定是估算的执行计划,但是没有办法,我们只能先参考这个进行优化。 EXPLAIN PLAN FOR select * from emp; SELECT * FROM TABLE(DBMS_XPLAN.DISPLAY); 超级简单的执行计划,在不出结果时初步参考使用,属于无奈之举。 4 关于...
EXCEPTIONWHENOTHERSTHENDBMS_OUTPUT.PUT_LINE('getting sql_text from awr:'||SQLERRM); :sql_text :=NULL;END;/--sql_text as foundSELECT:sql_textFROMDUAL;--check is sql_text for sql is availableSETTERMON;SETECHOOFF;BEGINIF:sql_textISNULLTHENRAISE_APPLICATION_ERROR(-20100,'SQL_TEXT for SQL_...
1. Describe the following threats to the application environment: Buffer overflow Denial of Service Time-of-check to time-of-use attacks Malformed input attacks Object reuse Garbage collection Trap do What is the difference between printf() and println()?
DBMS_SQLTUNE.LOAD_SQLSET(:ss_name, baseline_ref_cursor); DBMS_OUTPUT.PUT_LINE('SQL tuning set '||:ss_name||' created.'); END; / -- display details of the SQL tuning set col PLAN_HASH_VALUE clear select SQLSET_NAME,SQLSET_OWNER,SQL_ID,PLAN_HASH_VALUE from dba_sqlset_statements...
Describe at least three functions that a Database Management System (DBMS) performs to help create an accurate and consistent view of data throughout an enterprise. Describe which of the seven primary product or process impacts of LCA you believe presents th...
• User-interface design:Another popular application of OOP has been in the area of designing graphical user interfaces such as Windows. C++ is mainly used for developing user-interfaces. • Developingcomputergames:OOP is also used for developing computer games such as Diablo, Startcraft and Wa...
Example 11-14, "EXPLAIN PLAN Output" is an example of the plan table output when using the UTLXPLS.SQL script. UTLXPLP.SQL This script displays the plan table output including parallel execution columns. DBMS_XPLAN.DISPLAY table function This function accepts options for displaying the plan ...
By reviewing execution plans, you can also validate the scalability of an application. If the database operations are dependent upon full table scans of tables that could grow quite large, then there may be scalability problems ahead. On the other hand, if large tables are accessed via selectiv...