Monday, November 26, 2007
21.What are mutating triggers ?
A trigger giving a SELECT on the table on which the trigger is written.
22.What are constraining triggers ?
A trigger giving an Insert / Update on a table having referential integrity constraint on the triggering table.
23.Describe Oracle database's physical and logical structure ?
Physical : Data files, Redo Log files, Control file.
Logical : Tables, Views, Tablespaces, etc.
24.Can you increase the size of a tablespace ? How ?
Yes, by adding datafiles to it.
25.Can you increase the size of datafiles ? How ?
No (for Oracle 7.0)Yes (for Oracle 7.3 by using the Resize clause ----- Confirm !!).
26.What is the use of Control files ?
Contains pointers to locations of various data files, redo log files, etc.
27.What is the use of Data Dictionary ?
Used by Oracle to store information about various physical and logical Oracle structures e.g. Tables, Tablespaces, datafiles, etc
28.What are the advantages of clusters ?
Access time reduced for joins.
29.What are the disadvantages of clusters ?
The time for Insert increases.
30.Can Long/Long RAW be clustered ?