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Space Management in Extents and Segments - DBArch Video 31 / DBPerf Video 13
 
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In this video you will understand about the following - Dictionary managed Vs Locally Managed Tablespaces - Manual Vs Automatic Segment Space Management - PCTFREE and PCTUSED - Row Migration and Row Chaining . Our Upcoming Online Course Schedule is available in the url below https://docs.google.com/spreadsheets/d/1qKpKf32Zn_SSvbeDblv2UCjvtHIS1ad2_VXHh2m08yY/edit#gid=0 Reach us at [email protected]
Views: 8110 Ramkumar Swaminathan
Relationships of Physical and Logical Storage structures in an Oracle Database - DBArch Video 22
 
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In this video you will understand the Relationships between the Physical files and Logical Components - Tablespace, Segments, Extents and Oracle Blocks in an Oracle Database . Our Upcoming Online Course Schedule is available in the url below https://docs.google.com/spreadsheets/d/1qKpKf32Zn_SSvbeDblv2UCjvtHIS1ad2_VXHh2m08yY/edit#gid=0 Reach us at [email protected]
Views: 13588 Ramkumar Swaminathan
System Change Number in Oracle Database - SCN - DBArch Video 26
 
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In this video you will understand what is System Change Number in an Oracle Database, and get to know about some of the uses of it. . Our Upcoming Online Course Schedule is available in the url below https://docs.google.com/spreadsheets/d/1qKpKf32Zn_SSvbeDblv2UCjvtHIS1ad2_VXHh2m08yY/edit#gid=0 Reach us at [email protected]
Views: 4976 Ramkumar Swaminathan
Define Segment, Extent, Block (Hindi) | Prof. Jayesh Umre
 
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Solution to the question submitted by students. Define Segment, Extent and Block? (RGPV Dec 2014,Dec 2010, Dec 2009) Sol. Block: A database block is the smallest unit of storage in Oracle. Oracle manages the storage space in the datafiles of its database in these units. The size of block is a specific number of bytes of storage within a given tablespace. The default block size is specified by the Oracle initialization parameter that is DB_BLOCK_SIZE. Extent: An extent is the next level of logical grouping in the database. An extent consist of one or more database blocks. When we enlarge a database object, the spece added to the object is allocated as an extent. Segment: Segment is a group of extents that form a database object that oracle treats as a unit, such as table. There are four types of segments- Data segment – It is a storage part. Index segment – Its hold all of its data. Temporary segment – It’s a temporary work space. Undo segment – to do transaction undo
Views: 1970 Study Everyday
How to find block sizes of all Oracle Database files
 
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Block size of control files and redo log files are not same as default block size of your oracle database. Understand the level of control we got to alter these block sizes from one of my real time activity. Many more interesting blogs at : www.orskl.com/blog Looking for Oracle DBA training: www.orskl.com/training WhatsApp: +919951696808
Views: 3260 OrSkl Academy
What are Data Blocks - DBArch Video 28
 
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In this video you will learn about an Oracle Database block, what are the possible sizes and how it impacts the tables. Also you will learn about setting up multiple block sizes and how to configure the Buffer Cache for a database with multiple block sizes . Our Upcoming Online Course Schedule is available in the url below https://docs.google.com/spreadsheets/d/1qKpKf32Zn_SSvbeDblv2UCjvtHIS1ad2_VXHh2m08yY/edit#gid=0 Reach us at [email protected]
Views: 3388 Ramkumar Swaminathan
How do I find the Overall Database size ?
 
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Hi friend in my today scenario you learn how to find the total database size ? Oracle database Unbeatable,Unbreakable Platform.. #Databasesize
Views: 2994 Oracle World
Parameter files in Oracle- Pfile & SPFile
 
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Hi Folks, Greetings!! I am professional part time oracle dba trainer and having good experience in oracle database administration. This is the right place to enroll yourself for Oracle DBA real time course. Please use following email ID for more details. Don’t hesitate to WhatsApp me any time. I will give you the best training and will create path to get DBA job easily. Enjoy the free YouTube video and connect with me for deep Oracle DBA knowledge. Mobile No : + 91 9960262955 (WhatsApp Number) EmailID: [email protected] Please visit my official website for oracle database training and hadoop blog. https://www.orcldata.com/ Please donate on below link if you think I am helping you with your career. https://www.paypal.me/ankushthavali OR Google Pay : 9960262955 OR Account No : 31347845762 IFSC: SBIN0012311 parameter file in oracle 11g what is parameter file in oracle parameter file definition pfile parameters in oracle 11g list of initialization parameters in oracle 11g static and dynamic parameters in oracle init.ora file location in oracle 12c spfile in oracle
Views: 767 ANKUSH THAVALI
Storage Concepts - Hard Disks Vs Flash/SSD , LUN and Tiered Storage concepts - ASM Video 3
 
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In this video you will learn about performance of Hard Disks and compare them with Flash/SSD Disks. You will also learn about how a LUN is created. At a high level you will learn what is a LUN and how tiered storage is created. . Our Upcoming Online Course Schedule is available in the url below https://docs.google.com/spreadsheets/d/1qKpKf32Zn_SSvbeDblv2UCjvtHIS1ad2_VXHh2m08yY/edit#gid=0 Reach us at [email protected]
Views: 9745 Ramkumar Swaminathan
Connection Pool with an Oracle Database - DBArch  Video 19
 
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In this video you will learn the concept of a Connection pool an application uses with a Database. You will learn the need for connection pool and how it helps in optimizing resource utilzation on the Database Server. You will learn that Logon and Logoff are the most resource intensive tasks in a database, and hence both tasks should be avoided during normal operations of the application and database. Our Upcoming Online Course Schedule is available in the url below https://docs.google.com/spreadsheets/d/1qKpKf32Zn_SSvbeDblv2UCjvtHIS1ad2_VXHh2m08yY/edit#gid=0 Reach us at [email protected]
Views: 8719 Ramkumar Swaminathan
What are the different types of Tablespaces in an Oracle Database - DBArch Video 23
 
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In this video you will understand about the different types of tablespaces and their use/purpose. . Our Upcoming Online Course Schedule is available in the url below https://docs.google.com/spreadsheets/d/1qKpKf32Zn_SSvbeDblv2UCjvtHIS1ad2_VXHh2m08yY/edit#gid=0 Reach us at [email protected]
Views: 11769 Ramkumar Swaminathan
Managing Database Structure -Tablespaces and Datafiles part 1st
 
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Hi friends in this video i am going to explain you how to create alter tablespace and datafile in oracle. #ManagingDatabaseStructure #TablespacesandDatafiles Oracle database Unbeatable,Unbreakable Platform..
Views: 11354 Oracle World
Oracle Data Storage
 
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CAPTIONS AVAILABLE - Full transcript (with some screenshots) available for a small fee at http://stores.lulu.com/konagora/. How Oracle stores your tables, how they grow, and how they can go bump.
Views: 8213 roughsealtd
Table Shrinking in Oracle Database
 
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1.Shrink the Table: Shrinking is started from 10g. In this method I’m using user u1 and table name sm1. Now I’m deleting some rows in sm1 COUNT ---------- 1048576 Table sm1 has 1048576 rows. [email protected]: delete from sm1 where deptno=10; 262144 rows deleted. I deleted above number of rows. Rows COUNT ---------- 786432 And I’m giving commit [email protected]: commit; Commit complete. So now we have 786432 rows in sm1 table. Now see the following command [email protected]: select OWNER,TABLESPACE_NAME,SEGMENT_NAME,SEGMENT_TYPE,BYTES/1024/1024||' mb'"space",BLOCKS,EXTENTS from dba_segments where tablespace_name like 'U%TS'; OWNER TABLESPACE_NAME SEGMENT_NAME SEGMENT_TYPE space BLOCKS EXTENTS ----- --------------- ------------- ------------- ------ ---------- ---------- U1 U1TS SM1 TABLE 29 mb 3712 44 After I deleted some rows in sm1 table still above result showing same values, so now our duty is shrink this table. This is done by following 2 ways, i By using COMPACT key word: In this method shrinking is done in two phases. In the first phase all fragmented space are just defragmented, but still the High Water Mark is persist with last used block only. That mean used free blocks are not de allocated and HWM is not updated here. Issue the following command before use shrink command. [email protected] alter table sm1 enable row movement; Table altered. There is particular use with above command, when we shrink the table all rows are moves to contiguous blocks, so here row movement should be done. By default the row movement is disabled for any table, so above command enabled the row movement. Then execute shrink command now. [email protected]: alter table sm1 shrink space compact; Table altered. Now see the space of table by using below command. [email protected]: select OWNER,TABLESPACE_NAME,SEGMENT_NAME,SEGMENT_TYPE,BYTES/1024/1024||' mb'"space",BLOCKS,EXTENTS from dba_segments where tablespace_name like 'U%TS'; OWNER TABLESPACE_NAME SEGMENT_NAME SEGMENT_TYPE space BLOCKS EXTENTS ----- --------------- ------------- ------------- ------ ---------- ---------- U1 U1TS SM1 TABLE 29 mb 3712 44 So here seems nothing happened with above shrink command, but internally the fragmented space is defragmented. But the high water mark is not updated, used free blocks are also not de allocated. For de allocating the used blocks we have to execute below command. This is the second phase. [email protected]: alter table sm1 shrink space; Table altered. Now see the space by using below command. [email protected]: select OWNER,TABLESPACE_NAME,SEGMENT_NAME,SEGMENT_TYPE,BYTES/1024/1024||' mb'"space",BLOCKS,EXTENTS from dba_segments where tablespace_name like 'U%TS'; OWNER TABLESPACE_NAME SEGMENT_NAME SEGMENT_TYPE space BLOCKS EXTENTS ----- --------------- ------------- ------------- ---------- ---------- ---------- U1 U1TS SM1 TABLE 20.8125 mb 2664 36 So now the space of sm1 table is reduced. Note: Actually the alter table sm1 shrink space command will complete these two phases of the shrinking of table at a time. But here we done shrink process in two phases because when we use alter table sm1 shrink space command the table locked temporarily some time period, during this period users unable to access the table. So if we use alter table sm1 shrink space compact command the table is not locked but space is defragmented. When we not in business hours issue the second phase shrink command then users are won’t get any problem. ii Because of above method the table dependent objects are goes to invalid state, to overcome this problem we have to use below command. [email protected]: alter table sm1 shrink space cascade; Table altered. The above command also shrinks the space of all dependent objects. We also do this in two phases like above two phases. See the below command. [email protected]: alter table sm1 shrink space compact cascade; Table altered. And then [email protected]: alter table sm1 shrink space cascade; Table altered. Transporting tablespace to different platform by Using RMAN : https://www.youtube.com/watch?v=CN401PUKK4A Oracle EBS apps Upgrade from 12 2 to 12 2 5 (start CD 51) : https://www.youtube.com/watch?v=zeO4goqR70Y Transport tablespace by using RMAN.: https://www.youtube.com/watch?v=YG6kWX7Par8
Views: 6945 BhagyaRaj Katta
SQLPLUS: LineSize & PageSize
 
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In this tutorial, you'll learn how to set linesize and pagesize . PL/SQL (Procedural Language/Structured Query Language) is Oracle Corporation's procedural extension for SQL and the Oracle relational database. PL/SQL is available in Oracle Database (since version 7), TimesTen in-memory database (since version 11.2.1), and IBM DB2 (since version 9.7).[1] Oracle Corporation usually extends PL/SQL functionality with each successive release of the Oracle Database. PL/SQL includes procedural language elements such as conditions and loops. It allows declaration of constants and variables, procedures and functions, types and variables of those types, and triggers. It can handle exceptions (runtime errors). Arrays are supported involving the use of PL/SQL collections. Implementations from version 8 of Oracle Database onwards have included features associated with object-orientation. One can create PL/SQL units such as procedures, functions, packages, types, and triggers, which are stored in the database for reuse by applications that use any of the Oracle Database programmatic interfaces. PL/SQL works analogously to the embedded procedural languages associated with other relational databases. For example, Sybase ASE and Microsoft SQL Server have Transact-SQL, PostgreSQL has PL/pgSQL (which emulates PL/SQL to an extent), and IBM DB2 includes SQL Procedural Language,[2] which conforms to the ISO SQL’s SQL/PSM standard. The designers of PL/SQL modeled its syntax on that of Ada. Both Ada and PL/SQL have Pascal as a common ancestor, and so PL/SQL also resembles Pascal in several aspects. However, the structure of a PL/SQL package does not resemble the basic Object Pascal program structure as implemented by a Borland Delphi or Free Pascal unit. Programmers can define public and private global data-types, constants and static variables in a PL/SQL package.[3] PL/SQL also allows for the definition of classes and instantiating these as objects in PL/SQL code. This resembles usage in object-oriented programming languages like Object Pascal, C++ and Java. PL/SQL refers to a class as an "Abstract Data Type" (ADT) or "User Defined Type" (UDT), and defines it as an Oracle SQL data-type as opposed to a PL/SQL user-defined type, allowing its use in both the Oracle SQL Engine and the Oracle PL/SQL engine. The constructor and methods of an Abstract Data Type are written in PL/SQL. The resulting Abstract Data Type can operate as an object class in PL/SQL. Such objects can also persist as column values in Oracle database tables. PL/SQL is fundamentally distinct from Transact-SQL, despite superficial similarities. Porting code from one to the other usually involves non-trivial work, not only due to the differences in the feature sets of the two languages,[4] but also due to the very significant differences in the way Oracle and SQL Server deal with concurrency and locking. There are software tools available that claim to facilitate porting including Oracle Translation Scratch Editor,[5] CEITON MSSQL/Oracle Compiler [6] and SwisSQL.[7] The StepSqlite product is a PL/SQL compiler for the popular small database SQLite. PL/SQL Program Unit A PL/SQL program unit is one of the following: PL/SQL anonymous block, procedure, function, package specification, package body, trigger, type specification, type body, library. Program units are the PL/SQL source code that is compiled, developed and ultimately executed on the database. The basic unit of a PL/SQL source program is the block, which groups together related declarations and statements. A PL/SQL block is defined by the keywords DECLARE, BEGIN, EXCEPTION, and END. These keywords divide the block into a declarative part, an executable part, and an exception-handling part. The declaration section is optional and may be used to define and initialize constants and variables. If a variable is not initialized then it defaults to NULL value. The optional exception-handling part is used to handle run time errors. Only the executable part is required. A block can have a label. Package Packages are groups of conceptually linked functions, procedures, variables, PL/SQL table and record TYPE statements, constants, cursors etc. The use of packages promotes re-use of code. Packages are composed of the package specification and an optional package body. The specification is the interface to the application; it declares the types, variables, constants, exceptions, cursors, and subprograms available. The body fully defines cursors and subprograms, and so implements the specification. Two advantages of packages are: Modular approach, encapsulation/hiding of business logic, security, performance improvement, re-usability. They support object-oriented programming features like function overloading and encapsulation. Using package variables one can declare session level (scoped) variables, since variables declared in the package specification have a session scope.
Views: 17581 radhikaravikumar
when checkpoint will occur in oracle database
 
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How to check current_scn number of database? ============================================= select CURRENT_SCN from v$database; select dbms_flashback.get_system_change_number from dual; select timestamp_to_scn(sysdate) from dual; how to check datafile header scn number? ========================================= select name,CHECKPOINT_CHANGE# from v$datafile_header; when checkpoint will occur? ============================ alter system switch logfile; alter database begin backup; alter database end backup; alter system checkpoint;(manual checkpoint) shutdown immediate;(when the database is down) what will happen when checkpoint occurs? ========================================= scn of datafile header will update;
Views: 3632 Praveen Biyyapu
Parameters for Archiving in an Oracle database - Backup&Reco Video 7
 
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In this video you will learn about the various parameters available to configure archiving of redo log files in an Oracle Database. Our Upcoming Online Course Schedule is available in the url below https://docs.google.com/spreadsheets/d/1qKpKf32Zn_SSvbeDblv2UCjvtHIS1ad2_VXHh2m08yY/edit#gid=0 Reach us at [email protected]
Views: 3925 Ramkumar Swaminathan
Collisions in Oracle GoldenGate - GG Video 22
 
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In this video you will learn about what are Collisions in Oracle GoldenGate. This typically when applying changes that were captured during an initial load. Further you will learn how to avoid collisions and if you cannot avoid, how do you manager or handle collisions. . Our Upcoming Online Course Schedule is available in the url below https://docs.google.com/spreadsheets/d/1qKpKf32Zn_SSvbeDblv2UCjvtHIS1ad2_VXHh2m08yY/edit#gid=0 Reach us at [email protected]
Views: 1981 Ramkumar Swaminathan
Oracle Database Tutorial 63 : Introduction to Tablespace In Oracle Database
 
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Introduction to tablespace in oracle database consist Brief intro of tablepsace, type of tablespace, Big and small file tablespace, intro of Data files in oracle By manish sharma RebellionRider ------------------------------------------------------------------------ ►►►LINKS◄◄◄ Blog : http://bit.ly/tablespace-introduction-rebellionrider Previous Tutorial ► Indexes https://youtu.be/F5NrQYD4a9g ------------------------------------------------------------------------- ►►►Help Me In Getting A Job◄◄◄ ►Help Me In Getting A Good Job By Connecting With Me on My LinkedIn and Endorsing My Skills. All My Contact Info is Down Below. You Can Also Refer Me To Your Company Thanks ------------------------------------------------------------------------- Copy Cloud referral link || Use this link to join copy cloud and get 20GB of free storage https://copy.com?r=kb4rc1 -------------------------------------------------------------------------- ►Make sure you SUBSCRIBE and be the 1st one to see my videos! -------------------------------------------------------------------------- Amazon Wishlist: http://bit.ly/wishlist-amazon ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ►►►Find me on Social Media◄◄◄ Follow What I am up to as it happens on https://twitter.com/rebellionrider https://www.facebook.com/imthebhardwaj http://instagram.com/rebellionrider https://plus.google.com/+Rebellionrider http://in.linkedin.com/in/mannbhardwaj/ http://rebellionrider.tumblr.com/ http://www.pinterest.com/rebellionrider/ You can also Email me at for E-mail address please check About section Please please LIKE and SHARE my videos it makes me happy. Thanks for liking, commenting, sharing and watching more of our videos This is Manish from RebellionRider.com ♥ I LOVE ALL MY VIEWERS AND SUBSCRIBERS
Views: 35757 Manish Sharma
Pack Rows Tightly setting PCTFREE correctly - With Demo - DBPerf Video 14
 
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In this video you will understanding about setting PCTFREE correctly and its impact in I/O and Memory / SGA utilization. At the end there is a demo to show you the same. Our Upcoming Online Course Schedule is available in the url below https://docs.google.com/spreadsheets/d/1qKpKf32Zn_SSvbeDblv2UCjvtHIS1ad2_VXHh2m08yY/edit#gid=0 Reach us at [email protected]
Views: 1457 Ramkumar Swaminathan
Reclaiming free space from innodb tables
 
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Reclaiming free space from innodb tables
Views: 157 Ask Guru
Instance Recovery in an Oracle Database - DBArch Video 10
 
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This video explains how Instance recovery happens in an Oracle Database. Our Upcoming Online Course Schedule is available in the url below https://docs.google.com/spreadsheets/d/1qKpKf32Zn_SSvbeDblv2UCjvtHIS1ad2_VXHh2m08yY/edit#gid=0 Reach us at [email protected]
Views: 15356 Ramkumar Swaminathan
Oracle Database and Instance Components - DBArch Video 3
 
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In this video you will learn about the Relationship between and Oracle Instance and an Oracle Database. You will know about the various components of an Instance ( SGA and Background Processes) and the various files of the Database and how they interact. Our Upcoming Online Course Schedule is available in the url below https://docs.google.com/spreadsheets/d/1qKpKf32Zn_SSvbeDblv2UCjvtHIS1ad2_VXHh2m08yY/edit#gid=0 Reach us at [email protected]
Views: 32443 Ramkumar Swaminathan
Redo Logs in an Oracle Database - DBArch Video 11
 
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This video explains the concepts of Redo Log Groups and Files in an Oracle Database. You will understand how Oracle Instance uses Redo Buffers and Logwriter to keep the redo in Redo Logs. Our Upcoming Online Course Schedule is available in the url below https://docs.google.com/spreadsheets/d/1qKpKf32Zn_SSvbeDblv2UCjvtHIS1ad2_VXHh2m08yY/edit#gid=0 Reach us at [email protected]
Views: 18310 Ramkumar Swaminathan
Multi-User Concurrent Transactions in an Oracle Database - DBArch  Video 12
 
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This video explains how an Oracle Database manages multi-user concurrent transactions. A database a multi-user environment and this video tells you how redo and data files are managed by an Oracle Instance / Database. Our Upcoming Online Course Schedule is available in the url below https://docs.google.com/spreadsheets/d/1qKpKf32Zn_SSvbeDblv2UCjvtHIS1ad2_VXHh2m08yY/edit#gid=0 Reach us at [email protected]
Views: 8246 Ramkumar Swaminathan
Simplified DBA-014- Database Architecture Physical and Logical   Explained
 
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A database storage structure could be divided into logical and physical structure. Physical structure consists of files on physical disks while logical structure resides in the database. Both can be managed separately. Each database is logically divided into two or more tablespaces. One or more data files are explicitly created for each tablespace to physically store the data. A database is divided into logical storage units called tablespaces, which group related logical structures or datafiles together. For example, tablespaces commonly group all of an application’s segments to simplify some administrative operations. At the finest level of granularity, an Oracle database’s data is stored in data blocks. One data block corresponds to a specific number of bytes of physical space on the disk. A data block size is specified for each tablespace when it is created. A database uses and allocates free database space in Oracle data blocks. When you create a table, a segment is created with the same name in the tablespace. This segment has one or more Extents of equal size. Each Extent has Oracle Data Blocks as per tablespace definition. A data block could be of size 8K, 16K, 32K, 64K etc.
Oracle Online Tutorial,Oracle Online Training,Oracle Online Training In India,Oracle Training Online
 
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Oracle Online Tutorial,Oracle Online Training,Oracle Online Training In India,Oracle Training Online Best Oracle Online Training in India by well experienced and real time experts. Srihitha Technologies provides the best Oracle online training from India by Oracle experts. for more details call 9885144200 / 9394799566. visit www.srihithatechnologies.com for Oracle online training demo information. Oracle is a program which maintains data for us and decides where it should go on the hard drive.In other words Oracle is a relational Database i.e. a collection of Data. The Oracle Database commonly referred to as Oracle RDBMS or simply as Oracle is an Object Relational Database Management System (ORDBMS) produced and marketed by Oracle Corporation. The Oracle RDBMS stores data logically in the form of tablespaces & physically in the form of data files. Tablespaces contain various types of memory segments like Data Segments, Index Segments, etc. Segments in turn comprise one or more extents. Extents comprise groups of contiguous data blocks. Data blocks form the basic units of data storage. Oracle database management trac ks its computer data storage with the help of information stored in the system tablespace. Oracle technology includes Application Server, which serves all the various applications available in the Oracle suite of products. This has high availability built into its server functionality so that the applications are reliable in their operation. The advantage of Oracle based technologies are that they are secure, reliable and conform to government requirements, and is hence the reason Oracle is used in a great number of government departments. What is Oracle And Why It Is Used?, what is Oracle?, Oracle tutorial for beginners, Oracle tutorial, What Is Oracle Tutorial?, what is Oracle definition, what is Oracle used for, what is Oracle Course, Oracle online training, Oracle online classes, Oracle online training youtube, Oracle online training classes, Oracle online training institute, Oracle online training in hyderabad, Oracle online training in india, Oracle online lectures,Oracle Online Tutorial,Oracle Online Training,Oracle Online Training From India, Oracle ,Oracle Online Training, Oracle Online Training From India,Oracle Training,Oracle Online Tutorial,Oracle Online Training,Oracle Online Training From India,Oracle Training Online,Learn Oracle
creating tablespace in oracle 12c
 
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As Oracle has evolved, the options for creating tablespaces have grown more complex, with more CREATE TABLESPACE options: You create tablespaces with the CREATE TABLESPACE command. Before you create the tablespace you should decide: 1. How big you wish the tablespace to be. 2. Where you want to put the datafile or datafiles that will be associated with that tablespace. 3. What you want to call the tablespace and the datafiles. We recommend that you include the following in the datafile name when you create the tablespace: 1. The name of the database 2. The name of the tablespace 3. A number that makes the datafile unique So, for a tablespace called USERS assigned to a database called BOOKTST we would have a datafile called booktst_users_01.dbf. Here is an example of creating such a tablespace using the create tablespace command: Note that we used 50m to indicate that we wanted to create the tablespace 50 Megabytes in size. You can also use the K symbol for Kilobytes, and the G symbol for Gigabytes. If you want to try to use the P symbol for a 50 Petabyte tablespace, we want to talk to you! There are several "create tablespace" options that determine how big the tablespace will be: Autoextend on: Creating a tablespace with autoextend on alleviates the potential problem of a database outage if the tablespace reaches maximum extents. You create a tablespace using autoextend with the autoextend on option. Using "create tablespace . . . autoextend on" will push the point of failure to the OS filesystem, which is good because you never want you database to hang because a tablespace cannot grow. With autoextend on, you only need to monitor the free space in the filesystem directory. Maxsize: This is the maximum size that the datafile can grow. We recommend creating a tablespace with maxsize unlimited to prevent a lock-up. Size: This is the size of the underlying data file for the tablespace. Blocksize: Specifying a larger blocksize will not result in a larger tablespace. See here on creating tablespaces with non-default blocksizes. Uniform size: This specifies the size that the data file will grow when it needs to extend. By default, an Oracle tablespace will not grow if it runs out of space. If you use up all your space, you are just out of luck unless you use the autoextend keyword to indicate that the tablespace may grow, on it?s own, dynamically. Here is an example of creating a tablespace that is set to autoextend:
Views: 5053 Mohammad Taseen
ROWID - DBArch Video 32
 
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In this video you will understand what is ROWID in an Oracle Database, where is it stored and what are its components. Our Upcoming Online Course Schedule is available in the url below https://docs.google.com/spreadsheets/d/1qKpKf32Zn_SSvbeDblv2UCjvtHIS1ad2_VXHh2m08yY/edit#gid=0 Reach us at [email protected]
Views: 3586 Ramkumar Swaminathan
Data Dictionary in Oracle | Oracle SQL Tutorial Videos | Mr.Vijay Kumar
 
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Data Dictionary in Oracle by Mr. Vijay Kumar "Naresh IT is the Best Software Training Institute for Hadoop, Salesforce, AWS, DevOps, Sprak, Data Science, Python, Tableau, RPA ,Java, C#.NET, ASP.NET, Oracle, Testing Tools, Silver light, Linq, SQL Server, Selenium, Android, iPhone, C Language, C++, PHP and Digital Marketing in Hyderabad, Chennai and Vijayawada, India which provides online and classroom training classes" For Registration : https://goo.gl/r6kJbB Visit Our Websites: http://nareshit.in/ http://nareshit.com/ Call: India- 8179191999, USA- 404-232-9879 Email: [email protected] Our Online Training Features: 1. Training with Real-Time Experts 2. Industry Specific Scenario’s 3. Flexible Timings 4. Soft Copy of Material 5. Share Video's of each and every session. For Registration : https://goo.gl/r6kJbB For more updates on courses and tips follow us on: Facebook: https://www.facebook.com/NareshIT Twitter: https://twitter.com/nareshitech Google+: https://plus.google.com/NareshIT For Registration : https://goo.gl/r6kJbB Call: India- 8179191999, USA- 404-232-9879 Email: [email protected]
Views: 2845 Naresh i Technologies
Oracle Tablespace Management | Important Things Explained Under 5 Mins | Oracle DBA
 
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Oracle DBA - Tablespace Management Explained Under 5 Mins.! (ASM) Managing Oracle Tablespace - Important Things Explained Under 5 Minutes - Oracle DBA Tablespace Management Important Things Explained Under 5 Minutes - Oracle DBA Thanks for Watching please Like, Subscribe and Share...
Views: 198 BoxCut Media
Simplest way to create Tables on Oracle 12c
 
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--EMPLOYEE TABLE CREATE TABLE "EMP" ( "EMPNO" NUMBER(4,0), "ENAME" VARCHAR2(10 BYTE), "JOB" VARCHAR2(9 BYTE), "MGR" NUMBER(4,0), "HIREDATE" DATE, "SAL" NUMBER(7,2), "COMM" NUMBER(7,2), "DEPTNO" NUMBER(2,0) ) SEGMENT CREATION IMMEDIATE PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255 NOCOMPRESS LOGGING STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT) TABLESPACE "USERS" ; REM INSERTING into EMP SET DEFINE OFF; Insert into EMP (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (5258,'ALEX','MANAGER',null,to_date('25-JAN-89','DD-MON-RR'),1500,500,null); Insert into EMP (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7875,'Aziz','MANAGER',7839,to_date('17-NOV-97','DD-MON-RR'),5000,1000,10); Insert into EMP (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7899,'HADI','PRESIDENT',null,to_date('09-MAY-99','DD-MON-RR'),9000,null,10); Insert into EMP (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (3576,'ABDURAUF','MANAGER',null,null,null,null,null); Insert into EMP (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (3131,'EBAD','CR',null,to_date('25-JAN-81','DD-MON-RR'),1500,500,null); Insert into EMP (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7955,'JOHNABRAHM','QWERT',null,to_date('18-JUN-20','DD-MON-RR'),2000,null,30); Insert into EMP (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (5952,'JENN','MANAGER',null,to_date('25-JAN-81','DD-MON-RR'),1500,500,null); Insert into EMP (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7369,'SMITH','CLERK',7902,to_date('17-DEC-80','DD-MON-RR'),800,null,20); Insert into EMP (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7499,'ALLEN','SALESMAN',7698,to_date('20-FEB-81','DD-MON-RR'),1600,300,30); Insert into EMP (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7521,'WARD','SALESMAN',7698,to_date('22-FEB-81','DD-MON-RR'),1250,500,30); Insert into EMP (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7566,'JONES','MANAGER',7839,to_date('02-APR-81','DD-MON-RR'),2975,null,20); Insert into EMP (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7654,'MARTIN','SALESMAN',7698,to_date('28-SEP-81','DD-MON-RR'),1250,1400,30); Insert into EMP (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7698,'BLAKE','MANAGER',7839,to_date('01-MAY-81','DD-MON-RR'),2850,null,30); Insert into EMP (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7782,'CLARK','MANAGER',7839,to_date('09-JUN-81','DD-MON-RR'),2450,null,10); Insert into EMP (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7788,'','ANALYST',7566,to_date('19-APR-87','DD-MON-RR'),3000,null,20); Insert into EMP (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7839,'KING','PRESIDENT',null,to_date('17-NOV-81','DD-MON-RR'),5000,null,10); Insert into EMP (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7844,'TURNER','SALESMAN',7698,to_date('08-SEP-81','DD-MON-RR'),1500,0,30); Insert into EMP (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7876,'ADAMS','CLERK',7788,to_date('23-MAY-87','DD-MON-RR'),1100,null,20); Insert into EMP (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7900,'JAMES','CLERK',7698,to_date('03-DEC-81','DD-MON-RR'),950,null,30); Insert into EMP (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7902,'FORD','ANALYST',7566,to_date('03-DEC-81','DD-MON-RR'),3000,null,20); Insert into EMP (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (7934,'MILLER','CLERK',7782,to_date('23-JAN-82','DD-MON-RR'),1300,null,10); Insert into EMP (EMPNO,ENAME,JOB,MGR,HIREDATE,SAL,COMM,DEPTNO) values (5230,'SCARLET','MANAGER',null,to_date('26-JAN-81','DD-MON-RR'),1600,600,null); CREATE UNIQUE INDEX "PK_EMP" ON "EMP" ("EMPNO") PCTFREE 10 INITRANS 2 MAXTRANS 255 COMPUTE STATISTICS STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT) TABLESPACE "USERS" ; ALTER TABLE "EMP" ADD CONSTRAINT "PK_EMP" PRIMARY KEY ("EMPNO") USING INDEX PCTFREE 10 INITRANS 2 MAXTRANS 255 COMPUTE STATISTICS STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT) TABLESPACE "USERS" ENABLE; ALTER TABLE "EMP" ADD CONSTRAINT "FK_DEPTNO" FOREIGN KEY ("DEPTNO") REFERENCES "DEPT" ("DEPTNO") ENABLE;
Views: 60 Fareed Ullah
Creating Tables Without Segments
 
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Understand Deferred Segment Creation Beginning with Oracle Database 11g Release 2, when you create heap-organized tables in a locally managed tablespace, the database defers table segment creation until the first row is inserted. In addition, segment creation is deferred for any LOB columns of the table, any indexes created implicitly as part of table creation, and any indexes subsequently explicitly created on the table. The advantages of this space allocation method are the following: 1.It saves a significant amount of disk space in applications that create hundreds or thousands of tables upon installation, many of which might never be populated. 2.It reduces application installation time.
Views: 303 Saurabh Joshi
Oracle Database Administration-TABLESPACE MANAGEMENT PART I
 
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Oracle Database Administration-TABLESPACE MANAGEMENT PART I
Views: 27 SooCloudy
dba interview questions & answer in oracle | Ten Minute Code
 
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Top Oracle DBA Interview Questions & Answer 1. Oracle DBA Characteristics Criteria Result Main storage structures Logical and Physical Architecture Grid architecture ACID Compliance Fully compliant Data stored as Data blocks, extents, segments and table spaces 2. What is Oracle? Oracle is a company. Oracle is also a database server, which manages data in a very structured way. It allows users to store and retrieve related data in a multi user environment so that many users can concurrently access the same data. All this is accomplished while delivering high performance. A database server also prevents unauthorized access and provides efficient solutions for failure recovery. A standby database is a database replica created by taking a backup of a primary database. 3. What is a Oracle Database? Oracle provides software to create and manage the Oracle database. The database consists of physical and logical structures in which system, user, and control information is stored. The software that manages the database is called the Oracle database server. Collectively, the software that runs oracle and the physical database are called the Oracle database system. A database buffer cache stores the data in memory for quicker access. The redo logs track and store all the changes made to the database. A Data Guard ensures data protection and high availability of data and control file records the physical structure of the database. Click on the above link to read more and to become a Oracle DBA. 4. What are the roles of DBA? DBA has the authority to create new users, remove existing users or modify any of the environment variables or privileges assigned to other users. • Manage database storage • Administer users and security • Manage schema objects • Monitor and manage database performance • Perform backup and recovery • Schedule and automate jobs 5. What are different Oracle database objects? • TABLES • VIEWS • INDEXES • SYNONYMS • SEQUENCES • TABLESPACES 6. What are the benefits of ORDBMS? The objects as such can be stored in the database. The language of the DBMS can be integrated with an object- oriented programming language. The language may even be exactly the same as that used in the application, which does not force the programmer to have two representations of his objects. 7. What is an Oracle index? An index is an optional structure associated with a table to have direct access to rows, which can be created to increase the performance of data retrieval. Index can be created on one or more columns of a table. 8. What are the Common Oracle DBA Tasks? As an Oracle DBA, you can expect to be involved in the following tasks: • Installing Oracle software • Creating Oracle databases • Performing upgrades of the database and software to new release levels • Starting up and shutting down the database • Managing the database’s storage structures • Managing users and security • Managing schema objects, such as tables, indexes, and views • Making database backups and performing recovery when necessary • Proactively monitoring the database’s health and taking preventive or corrective action as required • Monitoring and tuning performance In a small to midsize database environment, you might be the sole person performing these tasks. In large enterprise environments, the job is often divided among several DBAs, each with their own area of specialty, such as the database security administrator or database tuning expert. 9. List out the Tools for Administering the Database? The following are some of the products, tools, and utilities you can use in achieving your goals as a database administrator. -Oracle Universal Installer (OUI) The Oracle Universal Installer installs your Oracle software and options. It can automatically launch the Database Configuration Assistant to install a database. -Database Configuration Assistant (DBCA) The Database Configuration Assistant creates a database from templates that are Oracle supplied, or you can create your own. It enables you to copy a preconfigured seed database, thus saving the time and effort of customizing and generating a database from scratch. -Database Upgrade Assistant This tool guides you through the upgrade of your existing database to a new Oracle release. -Oracle Net Manager This tool guides you through your Oracle Net network configuration. -Oracle Enterprise Manager The primary tool for managing your database is Oracle Enterprise Manager, a web-based interface. After you have installed the Oracle software, created or upgraded a database, and configured the network, you can use Oracle Enterprise Manager as the single interface for managing your database. In addition, Oracle Enterprise Manager also provides an interface for performance advisors and an interface for Oracle utilities such as SQL*Loader and Recovery Manager.
Views: 406 Together Oracle
Oracle DB - Process
 
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Oracle DB - Process Watch More Videos at: https://www.tutorialspoint.com/videotutorials/index.htm Lecture By: Mr. Parth Panjabi, Tutorials Point India Private Limited
Can a data block accommodate rows of distinct tables?
 
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With a case study let us find the answer if Oracle Database BLOCK can accommodate rows from multiple tables. Really very important when dealing with tuning an Oracle database at storage level. Need Oracle DBA training? Then visit www.orskl.com or whatsapp +919951696808 FInd more interesting blogs at www.orskl.com/blog
Views: 861 OrSkl Academy
SQL Execution/Elapsed Time - DBPerf Video 11
 
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In this video you will undestand what is SQL Execution time. You will get to know about CPU time and Wait Time . Our Upcoming Online Course Schedule is available in the url below https://docs.google.com/spreadsheets/d/1qKpKf32Zn_SSvbeDblv2UCjvtHIS1ad2_VXHh2m08yY/edit#gid=0 Reach us at [email protected]
Views: 1938 Ramkumar Swaminathan
Global Temporary Tables in Oracle Database - DBArch Video 21
 
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Learn about Global Temporary Tables in Oracle Database. You will learn the internals of Global Temporary tables in Oracle database, and also a demo for the same. Our Upcoming Online Course Schedule is available in the url below https://docs.google.com/spreadsheets/d/1qKpKf32Zn_SSvbeDblv2UCjvtHIS1ad2_VXHh2m08yY/edit#gid=0 Reach us at [email protected]
Views: 6043 Ramkumar Swaminathan
Oracle Database tutorial 64: How To Create Permanent tablespace (Big file and small file)
 
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How to create big file and small file permanent tablepsace in oracle database by Manish sharma rebellionRider In this tutorial you will learn the process of big file and small file permanent tablespace creation with datafiles ------------------------------------------------------------------------ ►►►LINKS◄◄◄ Blog : http://bit.ly/permanent-tablespace-oracle-rebellionrider Script: https://copy.com/whfzfAeUtzy0JEoU Previous Tutorial ► Tablespace The Introduction : https://youtu.be/5i5RtUdxaHY ------------------------------------------------------------------------- ►►►Help Me In Getting A Job◄◄◄ ►Help Me In Getting A Good Job By Connecting With Me on My LinkedIn and Endorsing My Skills. All My Contact Info is Down Below. You Can Also Refer Me To Your Company Thanks ------------------------------------------------------------------------- Copy Cloud referral link || Use this link to join copy cloud and get 20GB of free storage https://copy.com?r=kb4rc1 -------------------------------------------------------------------------- ►Make sure you SUBSCRIBE and be the 1st one to see my videos! -------------------------------------------------------------------------- Amazon Wishlist: http://bit.ly/wishlist-amazon ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ►►►Find me on Social Media◄◄◄ Follow What I am up to as it happens on https://twitter.com/rebellionrider https://www.facebook.com/imthebhardwaj http://instagram.com/rebellionrider https://plus.google.com/+Rebellionrider http://in.linkedin.com/in/mannbhardwaj/ http://rebellionrider.tumblr.com/ http://www.pinterest.com/rebellionrider/ You can also Email me at for E-mail address please check About section Please please LIKE and SHARE my videos it makes me happy. Thanks for liking, commenting, sharing and watching more of our videos This is Manish from RebellionRider.com ♥ I LOVE ALL MY VIEWERS AND SUBSCRIBERS
Views: 17938 Manish Sharma
Alternate Storage Techniques and Indexes Overview - DB Arch 35 / DBPerf 18
 
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In this video you will understand the different ways in which data can be stored/organized in an Oracle database and an overview of Indexes. This is the Eleventh lecture of the Oracle Database Troubleshooting and Tuning Class which is available on Udemy at The Full course is available on Udemy at https://www.udemy.com/oracle-database-troubleshooting-and-tuning You can use Coupon Code YOUTUBETT for discount Our Upcoming Online Course Schedule is available in the url below https://docs.google.com/spreadsheets/d/1qKpKf32Zn_SSvbeDblv2UCjvtHIS1ad2_VXHh2m08yY/edit#gid=0 Reach us at [email protected]
Views: 1678 Ramkumar Swaminathan
Shared Server Configuration in Oracle Database - DBArch Video 18
 
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You will learn about the concept of Shared Servers and Dispatchers in an Oracle Database. This is a method of optimizing resources on the Database Server side when a user is connecting from a Thick Client ( application installed on a desktop). Our Upcoming Online Course Schedule is available in the url below https://docs.google.com/spreadsheets/d/1qKpKf32Zn_SSvbeDblv2UCjvtHIS1ad2_VXHh2m08yY/edit#gid=0 Reach us at [email protected]
Views: 7543 Ramkumar Swaminathan
Calculating DB size
 
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Views: 112 Holly H
www.e-forexx.com oracle dba
 
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open Enterprize manager another way usind cmd
Views: 207 ramiocp
Control File Backups - Manually - Backup&Reco Video 3
 
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In this video you will learn how to backup an Oracle Database control file. Our Upcoming Online Course Schedule is available in the url below https://docs.google.com/spreadsheets/d/1qKpKf32Zn_SSvbeDblv2UCjvtHIS1ad2_VXHh2m08yY/edit#gid=0 Reach us at [email protected]
Views: 3703 Ramkumar Swaminathan
What types of Applications connect to a Database - DBArch  Video 17
 
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In this video you will understand the difference between and Thick Client and a Middlware Client and the way they use Database connections. Our Upcoming Online Course Schedule is available in the url below https://docs.google.com/spreadsheets/d/1qKpKf32Zn_SSvbeDblv2UCjvtHIS1ad2_VXHh2m08yY/edit#gid=0 Reach us at [email protected]
Views: 7376 Ramkumar Swaminathan
Oracle Database 10g: New Features for Administrators
 
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This course introduces students to the new features in Oracle Database 10g - the database for Grid computing. Students learn how to use Oracle Database 10g new features to increase database availability, to simplify database performance monitoring and tuning through the use of Oracle Database 10g Advisors, and to offer simplified database manageability. The course also covers security and some development platform changes that students need to understand if applications running in databases support the related features. Hands-on practice sessions give students an opportunity to examine many of the new features for themselves. Course Objectives: Implement improved manageability features to simplify database management Utilize database advisors to provide proactive database monitoring Increase data availability through Oracle Database 10g features that offer improved point in time recovery Assist developers using Oracle Database 10g features in their applications ________________________________________ Course Topics: Introduction How DBAs Spend Their Time Oracle Database 10g Manageability Goals Oracle Database 10g Solution: Self-Managing Database Grid Computing Oracle Database 10g: The Database for the Grid Installation Installation Performance Enhancements Installation New Feature Support Automatic pre & post install validations CD pack contents Server Configuration Database Features Usage Tracking Automatic Enterprise Manager Configuration Simplified Initialization Parameters Simplified Database Install Load and Unload Data Cross-platform Transportable Tablespaces External Tables Unload DataPump Export and Import Utilities Automatic Management Automatic Checkpoint Tuning Automatic Database Diagnostic Monitor Automatic Shared Memory Tuning Automatic Optimizer Statistics Collection Automatic Undo Retention Manageability Infrastructure Advisory Framework Automatic Routine Administration Tasks Server-generated Alerts / Threshold-based Alerts Automatic Workload Repository Application Management and Availability SQL Access Advisor SQL Tuning Advisor New performance overview charts in EM Rule-based optimization (RBO) obsolescence SQL Support for Analytical Applications MERGE Command Enhancements Partitioned Outer Join Integrating Interrow Calculations in SQL Summary Management Enhancements System Resource Management Setting Idle Timeouts Switching Back to the Initial Consumer Group at End of Call Database Resource Manager - Adaptive Consumer Group Mapping Monitoring the Resource Manager The Scheduler Core Scheduler Features Privileges for Scheduler Components Calendaring Expressions Advanced Scheduler Concepts Space Management Segment Advisor New Segment Resource Estimation Online Segment Shrink Proactive Tablespace Management Undo Advisor Sorted Hash Clusters Improved VLDB Support Bigfile Tablespace Enhanced Partition Management in Enterprise Manager Global Partitioned Indexes - Hash Partitioning Local Partitioned Indexes Manageability Improvements Temporary tablespace groups RMAN Enhancements Flash Backup and Recovery Backup Compression Drop Database Automatic Channel Failover for Backup & Restore Incrementally Updated Backups Simplified Recovery Through Resetlogs Flashback Any Error Flashback Database Flashback Table Flashback Versions Query Flashback Transaction Query Flashback Drop General Storage Management Rename Tablespace Redo Logfile Sizing Advisor SYSAUX Tablespace Copying Files using the Database Server Automatic Storage Management Data mirroring with ASM ASM Dynamic Rebalancing ASM Striping ASM General Architecture ASM Disk Groups Failure Groups Maintain Software Oracle Database 10g Upgrade Paths Easy Upgrade (key DBUA features / one script upgrade) Upgrade Information Tools (pre/post) Security Enhancements VPD Static and Dynamic Policies Column-level VPD Uniform Audit Trail Miscellaneous New Features Transaction Monitoring End-to-End Tracing Logminer Enhancements Resumable Space Allocation Enhancements Regular Expression functions
Views: 10157 critiquemusicale
Difference Between Delete and Truncate
 
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Below is link for Useful Pl/SQL Books http://goo.gl/XMy0tt ---------------------------------------------------------- Difference Between Delete and Truncate in Detail On bigger picture they serve the same purpose but there are many Differences listed with examples Point Delete Truncate 1. Data Recovery Delete: Come under the DML Category, we need to commit or Rollback explicitly to make the changes permanent, so we can recover the data by Rollback command fully with in a session or up to a point if Save Points are used Fall In DDL Category (DDL Command issue the Auto commit implicitly) so no chances of Recovery even not using the Flashback table method. But Truncate operations are also logged , they didn’t generate redo SQL but they are logged , view for truncated data info V$LOGMNR_CONTENTS 2. Data Removal Delete Can remove all or selected data using the Where Clause predicates. Or we can say delete any subset of rows We can Truncate complete table or a partition or sub partition of a table. 3. Speed Delete is Slower because oracle maintain the redo logs for Read Consistency (so that every session connected can see a consistent data at a given point of time ) Delete is very time consuming activity especially when table have numerous indexes and Triggers associated with table Faster as no data logs are maintained no associated trigger firing. 4. DML Triggers Firing DML (Delete) triggers associated with table will fire. DML Trigger will not fire in case of truncate method. 5. Flashback Technology Data can be recovered even after commit operation using Flashback Table options Flashback_transaction_query table will give what to recover and up to which point. Data cannot be recovered in truncate method by Flashback table option. 6. Referential Integrity Constraint Behavior if we don’t have related data in child table then we can delete the data from the parent table or we have variants like On Delete Cascade & on Delete set Null. We can’t truncate a table with enable Referential Integrity Constraint, even there is no data in the child table, we have to disable or drop the constraint if we want to truncate the table. Exception: Truncate is possible if the FK is self-referential means primary key and foreign key are on the same table. 7. Space De allocation or Space Utilization No extent reset with delete when deleting rows from a table, extents are not de allocated, So if there were 50 extents in the table before the deletion, there will still be 50 after the deletion. Truncate: When a table is truncated it will free the space allocated except in case of reuse storage clause. This space can subsequently be used only by new data in the table or cluster resulting from insert or update operations .All extents are de allocated leaving only the extents specified when the table was originally created .Example So if the table was originally created with min extents 3, there will be 3 extents remaining when the tables is truncated. When you truncate a table, NEXT is automatically reset to the last extent deleted. 8. High Water Mark Delete will not reset the high water mark Truncate will reset the High Water mark which is very important for performance point of view as in case of full table scan and full index scan oracle will read all the block under high water mark this makes a lot of difference in terms of performance. 9. Cluster No as such restriction with delete. You cannot individually truncate a table that is part of a cluster. You must truncate the cluster, Delete all rows from the table, or drop and re-create the table. 10. Information Capturing Delete : we can capture the row information what we have deleted using Delete Method, f you are deleting multiple records then use composite data types (collections & records) Truncate Don’t have this feature of capturing the deleted records. 11. Function Based Index Impact DELETE You cannot delete rows from a table if a function-based index on the table has become invalid. You must first validate the function-based index. Truncate: No as such restriction 12. UNUSABLE Indexes Delete no as such feature. Truncate if table is not empty then truncate make all unusable indexes to useable. 13. Complex views You cannot delete data from a Complex view except through INSTEAD OF triggers. But we can delete data from simple Views and MV. We cannot truncate a view simple or complex but you can truncate MV with special Features like Preserve MV Logs and Purge MV Logs. 14. Privileges Delete You need to provide delete table privilege on object. Truncate you must have drop table privilege there is no truncate table privilege exists. 15. Domain Index No as such restriction You cannot truncate the object having domain index in invalid or In progress state
Views: 13323 Ram Gupta