oracle sql joins tutorial

The difference between delete and truncate: delete generates rollback. If you delete a table with a large amount of data, it will take up a lot of rollback segments. truncate is a DDL operation and does not generate rollback, which is faster. Oracle Clearing table SQL statement and difference between truncate and delete Truncate table [table name] Use the truncate statement to delete all rows from t

/1024) "MB", t.* from Dba_segments t where segment_name in (select Index_name from Dba_par T_indexes WHERE table_name = ' T2 ') Order by segment_name, Partition_name; Related content Reference: SQL Tuning Basic Overview 04-oracle table types and introduction SQL Tuning Basics Overview 05-oracle Index typ

Because of the work required, today you will install SQL Server 2005 on your computer. Previous projects are using ORACLE,MS database is not really how to use, the installation of Oracle has been pro, but installed SQL Server seems to have a little trouble, so log down to stay in reserve.-------------------------------

The following is the data Guard CPU/PSU patch installation method for a detailed analysis of the introduction, the need for friends can refer to the next Non-Data guard patch installation tutorials refer to the [Oracle] CPU/PSU patch installation detailed tutorial, where Data Guard requires primary and standby to be patched at the same time, so the steps are more complex and the main steps are as follows:1

Link navigation in this series:[Lone solitary Nine swords] Oracle Knowledge Point Grooming (a) table space, user[Lone solitary Nine swords] Oracle Knowledge Point Grooming (ii) connection of databases[Lone solitary Nine swords] Oracle Knowledge Point Grooming (iii) Import, export[Lone solitary Nine swords] Oracle Knowl

For non-Data Guard patch installation tutorials, refer to [Oracle] CPU/PSU patch installation detailed tutorial. Data Guard requires both Primary and Standby patches, so the steps are more complex, the main steps are as follows:1. Stop the log transmission service in Primary;2. Shut down the Standby database, patch the Standby software (Note: Do not patch the Standby database), start the standby status as m

Oracle expdp/impdp Test Library Build tutorial, expdpimpdp Recently, the customer needs to build a test database, so they just need to organize their experience.I. Test Database creation: To create a database in windows, it is best to run the database with the Administrator permission, even if the Administrator logs on to the database. In general, it is best to ensure that the database is created using the

SQL FOREIGN key Foreign Key instance tutorial The key constraints of foreign SQLThe foreign key is at one table point and the primary key is seated in another. Let us illustrate the foreign key with an example. Take a look at the following two tables: In the People table: LastName FirstName Address City1 Hansen Ola Timoteivn Sandnes2 Svendson Tove Borgvn Sandnes3 Pettersen Kari Storgt Stavanger Order t

Ora-12541:tns when connecting to an Oracle server with a client tool such as Pl/sql Developer: No listener error, as shown in the following figure: It turns out that the Oracle Monitor did not start and the connection was successful after the reboot, and share with you how to initiate Oracle's listening. 1. On the host installing the

Beginner: Oracle getting started tutorial 1. note: To DELETE a TABLE, you must use the truncate table Name When deleting all the data in a TABLE. Because the drop table and DELETE * from table names are used, the occupied space of the table in TABLESPACE is not released, and the DROP operation is performed several times. After the DELETE operation, the space of hundreds of megabytes on the table space is ex

operation. This indicates, the ' view ' would be selected from directly as opposed to being broken-to-joins on the base table S. A number of constructs make A view non mergeable. Inline views is also non mergeable. 4.partition View --Partitioned view Partition views is a legacy technology that were superceded by the partitioning option. This section of the article are provided as reference for such legacy systems. Attached:

Oracle Data Warehouse creation tutorial. How to create a data warehouse, create an example, think of graduation design requirements, recently began Oracle's Warehouse modeling practice, detailed records of the graphical interface Oracle database 12C Data Warehouse creation process. This tutorial can be successfully c

Oracle empty table SQL statements and truncate and delete differences TRUNCATE TABLE [name] Remove or cluster all rows from the table using the TRUNCATE statement. By default, the Oracle Database tutorial also performs the following tasks: The only exception to deallocate is that all of the storage space used in