What does ROLLBACK do ?

What does ROLLBACK do ?
by

1 Answer

Answer :

ROLLBACK retracts any of the changes resulting from the SQL
statements in the transaction.
by

Related questions

What are the uses of rollback segment?

Description : What are the uses of rollback segment?

Last Answer : A database contains one or more rollback segments to temporarily store "undo" information.

What are the uses of rollback segment?

Description : What are the uses of rollback segment?

Last Answer : A database contains one or more rollback segments to temporarily store "undo" information.

What is rollback segment?

Description : What is rollback segment?

Last Answer : A database contains one or more rollback segments to temporarily store "undo" information.

Is it possible to use Transaction control Statements such a ROLLBACK or COMMIT in Database Trigger ? Why ?

Description : Is it possible to use Transaction control Statements such a ROLLBACK or COMMIT in Database Trigger ? Why ?

Last Answer : It is not possible. As triggers are defined for each table, if you use COMMIT of ROLLBACK in a trigger, it affects logical transaction processing.

How will you create multiple rollback segments in a database ?

Description : How will you create multiple rollback segments in a database ?

Last Answer : Create a database which implicitly creates a SYSTEM Rollback Segment in a SYSTEM tablespace. Create a Second Rollback Segment name R0 in the SYSTEM tablespace. Make new rollback segment ... ) for rollback segments. Deactivate Rollback Segment R0 and activate the newly created rollback segments.

What is a Rollback segment entry ?

Description : What is a Rollback segment entry ?

Last Answer : It is the set of before image data blocks that contain rows that are modified by a transaction. Each Rollback Segment entry must be completed within one rollback segment. A single rollback segment can have multiple rollback segment entries.

How will you monitor rollback segment status ?

Description : How will you monitor rollback segment status ?

Last Answer : Querying the DBA_ROLLBACK_SEGS view IN USE - Rollback Segment is on-line. AVAILABLE - Rollback Segment available but not on-line. OFF-LINE - Rollback Segment off-line INVALID - Rollback ... corupted. PARTLY AVAILABLE - Contains data from an unresolved transaction involving a distributed database.

How will you force database to use particular rollback segment ?

Description : How will you force database to use particular rollback segment ?

Last Answer : SET TRANSACTION USE ROLLBACK SEGMENT rbs_name.

I've lost some Rollback Segments, how can I get my DB back? (for DBA

Description : I've lost some Rollback Segments, how can I get my DB back? (for DBA

Last Answer : Re-start your database with the following INIT.ORA parameter if one of your rollback segments is corrupted. You can then drop the corrupted rollback segments and create it from scratch. ... Please contact Oracle Support before using it. _Corrupted_rollback_segments = (rbs01, rbs01, rbs03, rbs04)

What is Rollback Segment ?

Description : What is Rollback Segment ?

Last Answer : A Database contains one or more Rollback Segments to temporarily store "undo" information.

What are your thoughts on this 13th month pension rollback?

Description : I find it ridiculous that they want to return it for years (weekly). What is the point of this?

Last Answer : The principle of continuity is applied. Help for the elderly. More than anything, however, it can also be a good marketing ploy for your next choice.

In SQL, the CREATE TABLESPACE isused A. to createa place in the databasefor storageof scheme objects, rollback segments, andnaming the data files to comprise the tablespace B. to createa database trigger C. to add/rename data files, to change storage D. All of theabove E. None of the above

Description : In SQL, the CREATE TABLESPACE isused A. to createa place in the databasefor storageof scheme objects, rollback segments, andnaming the data files to comprise the tablespace B. to createa database trigger C. to add/rename data files, to change storage D. All of theabove E. None of the above

Last Answer : to createa place in the databasefor storageof scheme objects, rollback segments, andnaming the data files to comprise the tablespace

Point out the wrong statement. a) Taken as a unit, “Request => Process => Response” is not an atomic transaction b) A coherent transaction either succeeds and is enacted, or fails and is rolled back c) When rollback is not possible due to optimistic transaction commitment in a multiuser application, durability requires correcting the condition d) None of the mentioned

Description : Point out the wrong statement. a) Taken as a unit, Request => Process => Response is not an atomic transaction b) A coherent transaction either succeeds and is enacted, or ... transaction commitment in a multiuser application, durability requires correcting the condition d) None of the mentioned

Last Answer : Taken as a unit, “Request => Process => Response” is not an atomic transaction

What are the various types of RollBack Segments ?

Description : What are the various types of RollBack Segments ?

Last Answer : Public Available to all instances Private Available to specific instance

Can you Rollback to any savepoint ?

Description : Can you Rollback to any savepoint ?

Last Answer : Yes.

An insert statement followed by a create table statement followed by rollback ? Will the rows be inserted ?

Description : An insert statement followed by a create table statement followed by rollback ? Will the rows be inserted ?

Last Answer : No.

What are the states of a rollback segment ? What is the difference between partly available and needs recovery ?

Description : What are the states of a rollback segment ? What is the difference between partly available and needs recovery ?

Last Answer : The various states of a rollback segment are : ONLINE, OFFLINE, PARTLY AVAILABLE, NEEDS RECOVERY and INVALID.

What are the min. extents allocated to a rollback extent ?

Description : What are the min. extents allocated to a rollback extent ?

Last Answer : Two

What is Rollback Segment?

Description : What is Rollback Segment?

Last Answer : A Database contains one or more Rollback Segments to temporarily store “undo” information.

There is one application, which runs on a single terminal. There is another application that works on multiple terminals. What are the test techniques you will use on the second application that you would not do on the first application? A. Integrity, Response time B. Concurrency test, Scalability C. Update & Rollback, Response time D. Concurrency test, Integrity

Description : There is one application, which runs on a single terminal. There is another application that works on multiple terminals. What are the test techniques you will use on the second application that ... B. Concurrency test, Scalability C. Update & Rollback, Response time D. Concurrency test, Integrity

Last Answer : C. Update & Rollback, Response time

What does "jumps off the screen" mean?

Description : What does "jumps off the screen" mean?

Last Answer : answer:AMD is a relatively small manufacturer but well established in the industry. In this context, AMD jumps off the screen at the guy doing the research into acquiring companies for ... chip manufacturing division, but AMD is the one that really stands out from an acquisition perspective.

How to add conditions in select statement in oracle?

Description : How to add conditions in select statement in oracle?

Last Answer : Just add the decode

How can I dump an oracle schema to a LOCAL file over a network connection from sqlplus?

Description : How can I dump an oracle schema to a LOCAL file over a network connection from sqlplus?

Last Answer : By connecting and spooling are you excluding the exp/imp commands (or expdb/impdb in 10g)?

What are the two ways to incorporate images into a oracle forms application?

Description : What are the two ways to incorporate images into a oracle forms application?

Last Answer : Boilerplate Images Image_items

Can one export a subset of a table? (for DBA

Description : Can one export a subset of a table? (for DBA

Last Answer : From Oracle8i one can use the QUERY= export parameter to selectively unload a subset of the data from a table. Look at this example: exp scott/tiger tables=emp query=\"where deptno=10\"

What are the types of visual attribute settings?

Description : What are the types of visual attribute settings?

Last Answer : Custom Visual attributes Default visual attributes Named Visual attributes. Window

How does one use the import/export utilities? (for DBA

Description : How does one use the import/export utilities? (for DBA

Last Answer : Look for the "imp" and "exp" executables in your $ORACLE_HOME/bin directory. One can run them interactively, using command line parameters, or using parameter files. Look at the imp/exp parameters ... and export data with the "Schema Manager" GUI that ships with Oracle Enterprise Manager (OEM).

what is a display item?

Description : what is a display item?

Last Answer : Display items are similar to text items but store only fetched or assigned values. Operators cannot navigate to a display item or edit the value it contains.

What is import/export and why does one need it? (for DBA

Description : What is import/export and why does one need it? (for DBA

Last Answer : The Oracle export (EXP) and import (IMP) utilities are used to perform logical database backup and recovery. They are also used to move Oracle data from one machine, database or schema to ... corruption. Ensure that all the data can be read. . Transporting tablespaces between databases . Etc.

Are there any troubleshooting tips for OEM? (for DBA

Description : Are there any troubleshooting tips for OEM? (for DBA

Last Answer : . Create the OEM repository with a user (which will manage the OEM) and store it in a tablespace that does not share any data with other database users. It is a bad practice to create ... successfully. Check the log to see the results of the execution rather than relying on this status.

Where can one get more information about TCL? (for DBA

Description : Where can one get more information about TCL? (for DBA

Last Answer : One can write custom event checking routines for OEM using the TCL (Tool Command Language) language. Check the following sites for more information about TCL: . The Tcl Developer Xchange - ... the OraTCL package . Tom Poindexter's Tcl Page - Oratcl was originally written by Tom Poindexter

How does one start the Oracle Intelligent Agent? (for DBA

Description : How does one start the Oracle Intelligent Agent? (for DBA

Last Answer : One needs to start an OIA (Oracle Intelligent Agent) process on all machines that will to be managed via OEM. For OEM 9i and above:

What is the Oracle Intelligent Agent? (for DBA

Description : What is the Oracle Intelligent Agent? (for DBA

Last Answer : The Oracle Intelligent Agent (OIA) is an autonomous process that needs to run on a remote node in the network to make the node OEM manageable. The Oracle Intelligent Agent is ... events registered in Enterprise Manager; and . Executing tasks associated with jobs submitted to Enterprise Manager.

What are the types of SQL Statement ?

Description : What are the types of SQL Statement ?

Last Answer : Data Definition Language : CREATE,ALTER,DROP,TRUNCATE,REVOKE,NO AUDIT & COMMIT.

How does one backout events and jobs during maintenance slots? (for DBA

Description : How does one backout events and jobs during maintenance slots? (for DBA

Last Answer : Managemnet and data collection activity can be suspended by imposing a blackout. Look at these examples: agentctl start blackout # Blackout the entrire agent agentctl stop blackout # Resume normal monitoring ... management agentctl start blackout -s jobs -d 00:20 # Blackout jobs for 20 minutes

What are the pre requisites ?

Description : What are the pre requisites ?

Last Answer : I. to modify data type of a column ? ii. to add a column with NOT NULL constraint ? To Modify the datatype of a column the column must be empty. to add a column with NOT NULL constrain, the table must be empty.

What kind of jobs can one schedule with OEM? (for DBA

Description : What kind of jobs can one schedule with OEM? (for DBA

Last Answer : OEM comes with pre-defined jobs like Export, Import, run OS commands, run sql scripts, SQL*Plus commands etc. It also gives you the flexibility of scheduling custom jobs written with the TCL language.

Difference between SUBSTR and INSTR ?

Description : Difference between SUBSTR and INSTR ?

Last Answer : INSTR (String1,String2(n,(m)),INSTR returns the position of the mth occurrence of the string 2 instring1. The search begins from nth position of string1.SUBSTR (String1 n,m)SUBSTR returns a character string of size m in string1, starting from nth position of string1.

Should the OEM Console be displayed at all times (when there are scheduled jobs)? (for DBA

Description : Should the OEM Console be displayed at all times (when there are scheduled jobs)? (for DBA

Last Answer : When a job is submitted the agent will confirm the status of the job. When the status shows up as scheduled, you can close down the OEM console. The processing of the job is managed by the OIA ... that OEM will not be able to send e-mail and paging notifications when the Console is not started.

Explain UNION,MINUS,UNION ALL, INTERSECT ?

Description : Explain UNION,MINUS,UNION ALL, INTERSECT ?

Last Answer : INTERSECT returns all distinct rows selected by both queries.MINUS - returns all distinct rows selected by the first query but not by the second.UNION - returns all distinct rows selected by either queryUNION ALL - returns all rows selected by either query, including all duplicates.

WHY USE RMAN ? (for DBA

Description : WHY USE RMAN ? (for DBA

Last Answer : No extra costs Its available free ?RMAN introduced in Oracle 8 it has become simpler with newer versions and easier than user managed backups ?Proper security ?You are 100% sure your ... what need to backed up Knows what is required for recovery Knows what backups are redundant

WHAT IS RMAN ? (for DBA

Description : WHAT IS RMAN ? (for DBA

Last Answer : Recovery Manager is a tool that: manages the process of creating backups and also manages the process of restoring and recovering from them.

What is the basic structure of PL/SQL ?

Description : What is the basic structure of PL/SQL ?

Last Answer : PL/SQL uses block structure as its basic structure. Anonymous blocks or nested blocks can be used in PL/SQL.

What are the two parts of a procedure ?

Description : What are the two parts of a procedure ?

Last Answer : Procedure Specification and Procedure Body.

What are the datatypes a available in PL/SQL ?

Description : What are the datatypes a available in PL/SQL ?

Last Answer : Some scalar data types such as NUMBER, VARCHAR2, DATE, CHAR, LONG, BOOLEAN. Some composite data types such as RECORD & TABLE.

What are the return values of functions SQLCODE and SQLERRM ? What is Pragma EXECPTION_INIT ? Explain the usage ?

Description : What are the return values of functions SQLCODE and SQLERRM ? What is Pragma EXECPTION_INIT ? Explain the usage ?

Last Answer : SQLCODE returns the latest code of the error that has occurred. SQLERRM returns the relevant error message of the SQLCODE.

What is Overloading of procedures ?

Description : What is Overloading of procedures ?

Last Answer : The Same procedure name is repeated with parameters of different datatypes and parameters in different positions, varying number of parameters is called overloading of procedures. e.g. DBMS_OUTPUT put_line

s it possible to set a filter condition in a cross product group in matrix reports?

Description : s it possible to set a filter condition in a cross product group in matrix reports?

Last Answer : No

Can a repeating frame be created without a data group as a base?

Description : Can a repeating frame be created without a data group as a base?

Last Answer : No

What is an OLE?

Description : What is an OLE?

Last Answer : Object Linking & Embedding provides you with the capability to integrate objects from many Ms-Windows applications into a single compound document creating integrated applications enables you to use the features form .