rebuild mft

Create Table T1 as select * from EMP;Insert into T1 select * from T1;Create index I _empno on T1 (empno );Create index I _deptno on T1 (deptno ); @? \ RDBMS \ admin \ utlxplan SQL> explain Plan for alter index I _empno rebuild; Explained. SQL> select * from table (dbms_xplan.display ); Plan_table_outputBytes ---------------------------------------------------------------------------------------------------Bytes ----------------------------------------

2014-10-04 BaoxinjianI. Summary Index reconstruction is an issue that has been hotly debated. Of course, Oracle has its own views, and many of our DBAs follow this guideline to rebuild the index, which is that Oracle recommends rebuilding the index in 2 scenarios where the index depth exceeds level 4 and the deleted index entry occupies at least 20% of the total number of existing index entries. Recently, Oracle has also put forward some of the

Tags: des style blog http color io os using AR2014-10-04 BaoxinjianI. Summary Index reconstruction is an issue that has been hotly debated. Of course, Oracle has its own views, and many of our DBAs follow this guideline to rebuild the index, which is that Oracle recommends rebuilding the index in 2 scenarios where the index depth exceeds level 4 and the deleted index entry occupies at least 20% of the total number of existing index entries. Rece

When rebuild index VS. rebuild index online create index and rebuild index are used, the No. 4 lock will be applied to the original table, and the No. 3 lock will be applied to obj $ to prevent DML operations on the original table. Create index online and rebuild index online use a new temporary table to modify the ind

What are the general conditions for refactoring the index1. When the index is based on the table of DML operations frequently, over time, indexing efficiency is lower and higher, so you need to rebuild the index2. When the table is moved to another tablespace, the index to which the table is located becomes invalid and the index needs to be rebuilt Note: DML (manipulation Language) data manipulation language, one of the SQL classifications, DDL (data

This paper uses 10046 events to analyze the difference between ALTER INDEX rebuild and ALTER index rebuild online Alter index rebuild online is essentially a scan table rather than scanning an existing index block to achieve an indexed rebuild Alter INDEX rebuild only scans

Rebuild notes -- remove the value assigned to the parameter, and remove the value from the rebuild. This article is in the study of the summary, welcome to reprint but please note the Source: http://blog.csdn.net/pistolove/article/details/42497857 In the previous article, we introduced "breaking down temporary value changes". This article will introduce the refactoring method of "removing the value of a pa

Rebuild Data Center: "EXCEL export exception", rebuild data center export excel An exception occurred when the data center was restructured and the EXCEL export function was completed. When you run the statement to export an EXCEL file: Exception: Here, I would like to share with you the reason and solution. Please give me more advice! Cause:This exception occurs when the program runs the call transfer ad

CodeThe bad taste section describes common bad code and is basically popular with variousProgramming Language.6th ~ Chapter 11 summarizes some refactoring techniques in Java, which are based on the Reconstruction notes in the actual operation process.ProgramYou can choose to read it.Refactoring involves many opposite operations such as refining and inline functions, which may confuse people. What exactly do they follow? Congratulations, you have noticed this, which means we are notNerd. All you

Label:First, under what circumstances need to rebuild index 1, too many fragments (reference value: >20%)How index fragmentation occurs, move to the fragmentation and fill factor in the T-SQL query Advanced-sql Server index2, fill through the Low (reference value: Possible causes for the population to pass Low: ①. There is a partition table ③. The clustered index is not a digital ④. Less than the number of millions of data Ii. reconstruction of the in

CREATE OR REPLACE PROCEDURE p_rebuild_all_index (tablespace_name in VARCHAR2,-this is the table space name, and you can pass in NULL if you do not change the table spaceOnly_unusable in BOOLEAN)--is only an invalid index operationAsSQLT VARCHAR (200);BEGIN--only non-temporary indexesFor IDX in (SELECT index_name, Tablespace_name, STATUSFrom User_indexesWHERE temporary = ' N ') LOOP-If an invalid index is rebuilt, and if the index is not invalid, skipIF only_unusable = TRUE and IDX. STATUS GOTO C

There is a difference between the Reorganize and Rebuild of index.1, semantic differencesRebuild is re-created, releasing the space previously occupied by index, and re-applying for space to create index. Rebuilding an index means that a whole new set of pages are allocated for it.Reorganize is re-organized for use with index leaf level pages. Reorganizing an index compacts the Leaf-level pages back to their original specified fillfactor ant then rear

Tags: a note data BST strong important failure Logs ACL I. Overview Some time ago, there was a DBA friend after the Rebuild table (rename) work, the next morning the business is not working properly, the data can not be inserted restrictions and errors, later analysis found that the cause of the error is to use the rename way to rebuild the table, Other foreign KEY constraints referencing this table point