oracle tricky questions

Oracle creation triggers and frequently asked questions Triggers can be created inside Oracle DBA Studio Tools CREATE TRIGGERNameCreate trigger-creates a new triggerGrammarCREATE TRIGGER name {before | After} {event [OR ...] }On table for each {ROW | STATEMENT}EXECUTE PROCEDURE func (arguments)InputNameThe name of the trigger.TableThe name of the table.EventIns

Tags: http mil art New style query truncate SELECT index Recently participated in a number of interviews, summed up the competition in the Oracle development post most frequently asked what questions: 1, delete and truncate difference? 1) Truncate is a DDL statement. Delete is a DML statement; 2) Truncate speed is much faster than delete. The reason is that when we run the delete operation, all table data

Questions about using Oracle rollback segments in Delphi (urgent) Delphi/Windows SDK/API Http://www.delphi2007.net/DelphiDB/html/delphi_20061220125734202.html I wrote a Delphi Program There is no such thing in the program, but there is a loop, about 0.25 million. Each entry retrieves a no. and transmits it to an oracle procedure. This process includes inserting

: SELECT * from MYTB ORDER by MyCol nulls firstNULL Last: The null is queued at the bottom. Example: SELECT * from MYTB ORDER by MyCol nulls last"SQL Server":SQL Server considers null to be minimal.In ascending order : Null values are ranked first in the default.To arrange the back, then: the order by case if Col is null then 1 else 0 end, coldescending : null values default to the last.To line up in front, then: the order by case if Col is null and then 0 else 1 end, col descDescription1, is eq

oracle| problem Oracle interview Questions-Technical articles This is perhaps the article you have been looking forward to, while focusing on this part of the technical issues, please be sure to read the interview questions and answers about individuals. The answer here is not very comprehensive, these

, PDB1)Extract E1 successfully registered with database at SCN 2664333.Sql> select Capture_name,capture_user,status,start_scn,purpose from Dba_capture;Capture_name capture_user STATUS START_SCN PURPOSE----------------- ------------------ -------- ---------- -------------------Ogg$cap_e1 C # #GGADMIN ENABLED 2664333 GoldenGate Capture(3) testSql> Connect Pdb1_u1/[email protected]Connected.1) DMLsql> INSERT into S1 values (+);1 row created.Sql> commit;Commit complete.2) DDLsql> Create sequence SS1

This article is a collection of questions for Oracle technicians. The answer is for reference only ...... 1. Explain the differences between cold backup and hot backup and their respective advantages Answer: Hot Backup is applicable to databases in the archive mode. When the database is still in the working state, it is backed up. Cold backup refers to the backup after the database is closed, applicable to

Oracle stored procedures and questions 1. the overall structure of the create or replace procedure stored PROCEDURE name (parameter 1 in number, parameter 2 in number) IS variable 1 INTEGER: = 0; variable 2 DATE; BEGINEND stored PROCEDURE name 2. select into statement stores the select query results INTO variables. Multiple columns can be stored in multiple variables at the same time. One record is required

The following table lists the questions about updating field values with cursors in Oracle: [csharp] SQL> set pagesize 60; SQL> run; 1 * select * from employee www.2cto.com name salary ---------- SMITH 800 ALLEN 1600 WARD 1250 JONES 2975 MARTIN 1250 BLAKE 2850 CLARK 2450 SCOTT 3000 KING 5000 TURNER 1500 ADAMS 1100 JAMES 950 FORD 3000 MILLER 1300 already select 14 rows. In this table, if the SALARY column is

number and find the average score for each group of passing persons (grade >= 60) (average number of passing persons per course)3. Ask for an average of all courses for each student4. The average score for each student (exam result) Pass Course5. Average score for each student in each internal test (average of each course per learner)6. Check the average score of the students who have done the exam (find out if the student's course number (CID) appears in the group more than once) (each course

Recently participated in 4, 5 interviews, summed up the competition in the Oracle development post most frequently asked what questions:1. What is the difference between delete and truncate?1) Truncate is a DDL statement, and delete is a DML statement;2) Truncate speed is much faster than delete;The reason is that when we perform a delete operation, all table data is copied to the rollback table space first

The answer here is not comprehensive. These questions can be explained from multiple perspectives. Maybe you don't have to give a full answer during the interview, you only need to answer your questions to familiarize the interview examiner with Oracle concepts. 1. Explain the differences between cold backup and hot backup and their respective advantages Answer:

Novice Oracle, there will be two big questions: First, index range Scan (scan), second, index unique scan (indexed unique scan), the following two questions through a pictorial way to give you a detailed description: 1, Index range Scan (index range scan) Copy Code code as follows: Select Empno,ename from emp where empno >1orderby empno In th

to obtain the return status value of the command? Sqlcode = 0 97. How do I know the user's permissions? Select * From dba_sys_privs; 98. What is the difference between the Oracle9i downloaded from the internet and the standard edition sold on the market? In terms of functions, there is no difference, except that Oracle has clearly stipulated that Oracle products downloaded from the website cannot be used f

" CHAR(1 BYTE) NULL ,"id_card" CHAR(18 BYTE) NULL ,"email" VARCHAR2(30 BYTE) NULL ,"tel" CHAR(11 BYTE) NULL ,"address" VARCHAR2(64 BYTE) NULL ,"work_units" VARCHAR2(64 BYTE) NULL ,"monthly_income" NUMBER(8,2) NULL ,"bank_account" CHAR(20 BYTE) NULL ,"credit_rating" NUMBER(1) NULL) The results are as follows: It is therefore recommended that: 1. It is recommended that our visual operators develop the habit of writing handwritten SQL statements, and we d

Oracle Pen QuestionsFirst, single choice1. In Oracle, the following are not part of the set operator ().A.unionb. SUMC. MINUSD. INTERSECT2. In Oracle, execute the following statement:Selectceil (-97.342),Floor (-97.342),Round (-97.342),Trunc (-97.342)fromdual;The return value of which function is not equal to-97 ().A.ceil () B.floor () c.round (0) D.trunc ()3. Wh

Oracle interview questions: complex queries and instance analysis When you need to perform complex processing on the queried results, you can obtain the expected results by means of joint queries and subqueries. The following is a typical question, which is intended to inspire readers.1. Question requirements: Table NBA records TEAM Name and year of the winning team: TEAM YEAR ----------------------------

Oracle interview questions 1. Simple SQL query: 1): count the number of employees in each department Select Dept, count (*) from employee group by dept; 2): count the number of employees in each Department greater than one record Select Dept, count (*) from employee group by dept having count (*)> 1; 3): the name of the department where the employee whose salary exceeds 1200 Select E. first_name, salary, D.

This article originates from: http://www.dbasupport.com The answer here is not very comprehensive, these questions can be explained through a number of angles, perhaps you do not have to give a full answer in the interview process, only through your answers to the interviewer to understand your understanding of the Oracle concept. 1. Explain the different points of cold and hot backup and their advantages

Ora_oper Group ...So you can't log in with Sysoper. This requires that we create the Ora_oper group ourselves, and then add the Administrator user to the Ora_oper group.By default there is only ora_dba this groupProcedures such as the following:1, right button "computer"-"management"-"Local Users and Groups"-"group".2. Right button "group"-"new group ...".3. Enter the group name "Ora_oper" and join the member. Then select "Advanced" in the "Select User" pop-up box below.4, then select "Find Now