Oracle

Filter: Use the WHERE clause to filter out rows that do not meet the conditions. SQL> -- Use of the WHERE clause, coupled with filtering conditions, followed by the from table name SQL> -- where syntax select * | {distinct | express | clomn} from

######################### Enhanced Group by clause ######### ############### select [column,] group_function (column )... from table [Where condition] [group by [rollup] group_by_expression] [having having_expression]; [order by column]; -------

Importing and exporting Oracle Data imp/exp is equivalent to restoring and backing up ORACLE data.   The exp command can export data from the remote database server to the local DMP file, and the IMP command can import the DMP file from the local to

First, popularize the basic concepts: PL/SQL is a programming language that combines Procedural language and Structured Query Language (SQL. The PL/SQL block corresponds to a small piece of code. Applicable instructions: 1. Sometimes you may need to

Function Name: wmsys. wm_concat Purpose: Separate the values of the join columns with commas (,). Oracle 10 Gb introduction. Wm_concat can be used directly. The following describes the actual usage conditions. Create a test table and some test data

Import and export using exp/imp Note the following before starting exp/IMP: 1) This section uses Oracle 10 Gb as an example. 2) exp. IMP is the next executable file in the operating system and is stored in the/ORACLE_HOME/bin directory. So execute

Dba_xxx requires the permission to view the reports and views. Otherwise, the reports and views do not exist. 1. query all users (username, tablespace Information) Select * From dba_users; select * From all_users; // select * From user_users; 2.

Oracle has been in use for a long time, and many new users and tablespace are added. You need to clear them. For a single user and tablespace, you can use the following command.  Step 1: delete a user Drop user ××cascade Note: If a user is deleted,

OCR is equivalent to the Windows registry. For Windows, all software information, users, configurations, and security are stored in the registry. In the same way, all cluster-related resources, configurations, nodes, and Rac databases are stored in

Using shell scripts to monitor and manage Oracle databases will greatly simplify DBA workload, such as common instance monitoring, monitoring, and alarm log monitoring, and database backup, AWR report automatic mail, etc. This section describes how

Recently, some netizens are not very clear about the automatic memory management feature of Oracle SGA, probably because the automated management of Oracle 10g SGA translated at that time was quite cool, the following is still a description of this

In Oracle RAC, in addition to the TAF Method Based on the client, there is also the TAF Method Based on the server. You can regard the TAF method of the server as an upgraded version of the TAF method of the client. The TAF of the server must be

Recently, when using traditional imp tools to import data, a colleague always prompts to receive the skipping table prompt, that is, the table is skipped, rather than being rebuilt. The table object in the target database cannot be imported even if

The server Load balancer of the Oracle RAC server distributes new connection requests to the node with the smallest load based on the number of connection loads of each node in the RAC. When the database is running, the pmon process of each node in

Oracle Data Guard provides one or more slave databases for the production database (a copy of the database ), to ensure that data is not lost when the master database is unavailable or when exceptions occur, and continue to provide services through

ORA-12899 appears, is caused by character set, Chinese occupies 3 bytes in the UTF-8, zhs16gbk occupies 2 bytes, and the source DMP file character set is zhs16gbk inverted data, now to import to the target character set for the UTF-8 library, so

As we all know, to connect to Oracle using PL/SQL, you need to install the Oracle client software. Have you ever wondered whether to directly connect to Oracle without installing the Oracle client? You only need to download a software named Instant

From: http://blog.csdn.net/pan_tian/article/details/7699599   Another Oracle product was installed in the past two days. After restarting, it was found that the listening listener could not be started. After reinstalling the product, it was normal.

I have tried navicat premium, a new navicat product from the navicat family. It integrates Oracle, MySQL, and PostgreSQL management. I personally feel very strong (FAST )! In a whim, can Oracle import MySQL? First try: 1) A new Oracle connection

The SQL language is case insensitive. SQL statements can be written in one or more rows. Keywords cannot be abbreviated or the sub-statements of different branches are generally written in different branches. Use indentation to improve statement