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Which SELECT statement will the result 'elloworld' from the string 'HelloWorld'? A. SELECT SUBSTR( 'HelloWorld',1) FROM dual; B. SELECT INITCAP(TRIM ('HelloWorld', 1,1)) FROM dual; C. SELECT LOWER(SUBSTR('HellowWorld', 1, 1) FROM dual; D. SELECT LOWER(SUBSTR('HelloWorld', 2, 1) FROM dual; E. SELECT LOWER(TRIM ('H' FROM 'HelloWorld')) FROM dual; Answer: E Explanation: TRIM function accept a string describing the data you would like to trim from a column value. It can trim from both side of column value i.e. left and right. In the following statement this functionwill trim as SELECT LOWER(TRIM ('+' FROM 'HelloWorld')) FROM dual; From the above statement trim function will remove the character 'H' from 'HelloWorld' and LOWER function will convert the remaining character to lower case.

Processes Oracle uses many small (focused) processes to manage and control the Oracle instance. This allows for optimum execution on multi-processor systems using multi-core and multi-threaded technology. Some of these processes include: PMON - Process Monitor SMON - System Monitor ARCn - Redo Log Archiver LGWR - Redo Log Writer DBWn - Database Writer CKPT - Checkpoint process RECO - Recoverer CJQn - Job Queue Coordinator QMNn - Queue-monitor processes Dnnn - Dispatcher Processes (multiplex server-processes on behalf of users) Snnn - Shared server processes (serve client-requests) MMAN - Internal process (used for internal database tasks) LSP0 - Logical standby coordinator process (controls Data Guard log-application) MRP - Media-recovery process (detached recovery-server process) MMON - Memory-monitor process MMNL - Memory monitor light (gathers and stores AWR statistics) PSP0 - Process-spawner (spawns Oracle processes) RFS - Remote file server process (archive to a remote site) DBRM ...

Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER NOT NULL EMP_NAME VARCHAR2(30) JOB_ID VARCHAR2(20) SAL NUMBER MGR_ID NUMBER DEPARTMENT_ID NUMBER You want to create a SQL script file that contains an INSERT statement. When the script is run, the INSERT statement should insert a row with the specified values into the EMPLOYEES table. The INSERT statement should pass values to the table columns as specified below: EMPLOYEE_ID: Next value from the sequence EMP_ID_SEQEMP_NAME and JOB_ID: As specified by the user during run time, through substitution variables SAL: 2000 MGR_ID: No value DEPARTMENT_ID: Supplied by the user during run time throughsubstitutionvariable. The INSERT statement should fail if the user supplies a value other than20 or 50. Which INSERT statement meets the above requirements? A. INSERT INTO employees VALUES (emp_id_seq.NEXTVAL, '&ename', '&jobid', 2000, NULL,&did); B. INSERT INTO employees VALUES (emp_id_seq.NEXTVAL, '...

We can get the nth maximum value through query by using the combination of order by clause and rownum pseudo column. The Query following. SELECT MIN(columnname) FROM ( SELECT coumnname FROM tablename ORDER BY columnname DESC) WHERE rownum

Can we insert more than 1 row with 1 qyery in same table/diff tables? Yes, we insert more than 1 row with 1 qyery by using the following method? syntax INSERT ALL INTO tablename1 (fieldlist) VALUES (valuelist) INTO tablename2 (fieldlist) VALUES (valuelist) INTO tablename3 (fieldlist) VALUES (valuelist) SELECT * FROM DUAL; Example: insert all into student (sno, name) values (1, 'Raja') into student (sno, name) values (2 'Ravi') into student (sno, name) values (3, 'Balu') select * from dual; We can use more than 1 table also. insert all into student (sno, name) values (1, 'Raja') into student (sno, name) values (2 'Ravi') into emp (eno, name) values (1, 'Mani') select * from dual; Interview quesitions and answers, objective type questions with answers : http://atchaya.com/ora/orahome.html Oracle forum : http://atchaya.wikidot.com/forum/c-91091/discussion-about-oracle

Write a PL/SQL Program for the following output --*-- -***- ***** -***- --*-- Answer The output based on the value of 'n' declare n number(2) default 20; i number(2); j number(2); h number(2); s number(2); b varchar2(1) default 'I'; begin s := 1; if n mod 2 = 0 then n := n+1; end if; h := n/2 -1; for i in 1..n loop for j in 1..h loop dbms_output.put('-'); end loop; for j in 1..s loop dbms_output.put('*'); end loop; for j in 1..h loop dbms_output.put('-'); end loop; dbms_output.put_line(' '); if n = s then b := 'D'; end if; IF b='I' then s := s+2; h := h-1; else s := s-2; h := h+1; end if; end loop; end;

Evaluate the SQL statement DROP TABLE DEPT Which four statements are true of the SQL statement? A. You cannot roll back this statement. B. All pending transactions are committed. C. Al views based on the DEPT table are deleted. D. All indexes based on the DEPT table are dropped. E. All data in the table is deleted, and the table structure is also deleted. F.All data in the table is deleted, but the structure of the table is retained. G.All synonyms based on the DEPT table are deleted. Answer: A, B, D and E Explanation: A. You cannot roll back DROP TABLE statement. B. All pending transactions related on this table arecommitted. D. If the table is dropped, Oracle automatically drops any index, trigger and constraintassociated with the table as well. E. All data in the table is deleted, and the table structure is also deleted. Incorrect Answers C: All views based on the DEPT table become invalid, but they are not deleted. F: All data in the table is deleted, and the table structure is als...