Interview Questions Answers.ORG
Interviewer And Interviewee Guide
Interviews
Quizzes
Home
Quizzes
Interviews DB Oracle Interviews:Concepts and ArchitectureData AccessDatabase ArchitectureDatabase ManagementDatabase Security OracleDistributed ProcessingFlexfieldForms ReportsGeneral OracleMemory ManagementMTO-SAP Financial AccountingOCIOracle AOLOracle AROracle Backup RecoveryOracle D2KOracle DatabaseOracle Database DeveloperOracle DB OptimizationOracle DBAOracle DeveloperOracle ETLOracle Forms 3.0Oracle Forms 4.0Oracle GLOracle PL-SQLOracle RMANOracle ScenariosOracle SecurityOracle SQLOracle System ArchitectureOracle Technology Network (OTN)Programmatic ConstructsRAC (Real Application Clusters)SQL Plus
Copyright © 2018. All Rights Reserved
Oracle DBA Interview Question:
What is the difference between Truncate and Delete? Why is one faster?
Can we ROLLBACK both? How would a full table scan behave after?
Submitted by: AdministratorTruncate is nearly instantaenous, cannot be rolled back, and is fast because Oracle simply resets the HWM. When a full table scan is performed on a table, such as for a sort operation, Oracle reads to the HWM. So if you delete every single solitary row in 10 million row table so it is now empty, sorting on that table of 0 rows would still be extremely slow.
Submitted by: Administrator
Submitted by: Administrator
Copyright 2007-2024 by Interview Questions Answers .ORG All Rights Reserved.
https://InterviewQuestionsAnswers.ORG.
https://InterviewQuestionsAnswers.ORG.