oracle 12c new features for dba

Oracle Week Three: Table space management What does the name contain? : Improved table space management Table space management has been significantly improved, which can be attributed to a sparser SYSTEM, support for user-defined default tablespace, new Sysaux, and even renaming How many times have you been hurt by the user's creation of a non-SYS and system segment in the system table space? Before O

Why should we discuss this issue? It is rooted in history. Let's start with Oracle 10 Gb. Before 11G, if you want to add a new column to a large table and the new column has a default value, if you want to use alter table xx add xx_1 number default 1000; this type of statement settings will be very handy! Its action is to add a column and update the column. If th

Introduction Oracle Database 10 Gb provides five new flash back functions: Flash back version query, flash back transaction query, flash back deletion, flash back table and flash back database. Oracle Database 11gR1 provides an interesting new flash back function: Flash back data archiving, which allows an

Oracle Week 4th High-speed Export/import: Oracle Data Pump Data movement with Oracle Database 10g utility has been greatly improved. To date, the export/import toolset is still the least labor-intensive preferred utility for transferring data across multiple platforms, although people often complain about its slow speed. It is not surprising that imports simply

When you install an application that contains thousands of tables and indexes, if each table and index is initially allocated a 10 MB initialExtent. You will soon realize that if each object needs to allocate 10 MB of disk space during creation, it will take a lot of time to deploy the DDL. You may thinkOracle delays the initial extent allocation of each object until the actual insert records in the table. The only way to delay the generation of the object's initial segment is to useOracle Datab

recovery is enabled, the rollback occurs in parallel rather than serially, as if it occurred in a regular transaction rollback. The next task is to evaluate the completion time of the rollback process. View V$fast_start_transactions shows the transactions that are generated by the rollback failure transaction. A similar view v$fast_start_servers displays the number of parallel query servers that are processed for rollback. Both views are available in previous versions, but the

Column compression, a new compression mode, consumes more CPU power to achieve a smaller storage consumption, column compression for the application is transparent, the Data warehouse system is worth trying this new feature. 5. Data Pump Legacy Mode The original exp in the 11GR2 is no longer supported, and IMP is still allowed to use it. So 11GR2 provides a compatibility mode that allows the previous ex

New Feature of Oracle 11g R2: Deferred Segment Generation when you install an application that contains thousands of tables and indexes, if each table and index are initially allocated a 10 MB initial extent. You will soon realize that if each object needs to allocate 10 MB of disk space during creation, it will take a lot of time to deploy the DDL. You may think of letting

We have previously introduced the virtual columns and read-only tables in the new Oracle 11g feature. Today we will introduce another new feature, the combined trigger. In earlier versions of Oracle, you can use the FOLLOWS keyword to control the trigger execution sequence. For example: 01 CREATE OR REPLACE

In 11GR2, Oracle analysis functions are further enhanced. This article introduces the new analysis function Listagg. 11GR2 also adds an analytic function Listagg, the function of which implements string concatenation. In 11GR2, Oracle has finally implemented this analytic function: Sql> select * from V$version; BANNER ---------------------------------------

In 11GR2, Oracle analysis functions are further enhanced. This article introduces the new analysis function Nth_value. Previous versions of the analytic functions, which provided first_value and last_value functionality, and in 11GR2, Oracle added a nth_value feature that includes First_value and Last_value functions, You can also take any number of positive or

Last time we introduced the new feature of Oracle 11 GB-virtual columns. Today we will introduce another new feature-read-only tables. Read-Only tables are no different from normal tables, but no DML (Insert, Update, Delete) operations can be performed on any transactions. Before Oracle 11g, "read-only" is only valid f

Before Oracle 11g, adding a column to a large table and setting the default value would be a tragedy. sometimes you have to select the online redefinition function to achieve this requirement. adding new columns and setting the default values in 11 GB only allows you to modify the data dictionary to achieve this function, greatly improving the efficiency.Add 10g columns (default) SQL> select * from

1. Flashback drop Currently, Oracle10g provides the new flashback drop feature to accelerate the recovery of user error operations. The flashback drop function allows you to restore a dropped object from the current database. When you perform the drop operation, Oracle does not delete the object but automatically puts the object into the recycle bin. The recycle bin is a virtual container used to store

Label:1, version-based redefinition function (only R2 version)2. Force option for CREATE TYPE (only R2 version)3. Function Result Cache4. Continue statement: Exit the current iteration and continue looping the next iteration5. A sequence in a PL/SQL expression6. Dynamic SQL Enhancements7. New native compilation and simple data types8, Securefiles9, the enhancement of the trigger10. Automatic subroutine Insertion11, Pl/scope12. PL/SQL Hierarchical anal