Oracle

DBLINK is used in DBLINK and other syntax projects to summarize: When you want to access data in another database table across local databases, A remote database's dblink must be created in the local database. You can access the data in the remote

How to create an auto-incrementing primary key in Oracle 1. create a table and set the primary key. 2. create a sequence. 3. create trigger .www.2cto.com. For example: assume that the table name of the data table is tbl_name, the primary key column

Oracle Database Merge Into-how to use Sequence instead of "waste" 1. Problem Background: this problem is a problem introduced during Data Stage, the use of Merge Into is a waste of NextVal. Www.2cto.com 2. Test prerequisites: Create a script. SQL

After the oracle instance service was killed by 360, the method that was added to the System Service recently killed the server. As a result, many exe files and services may have been killed, including the cvsnt service and the oracle instance

Oracle queries table space usage SQL code select f. tablespace_name,. total, u. used, f. free, round (u. used/. total) * 100) "% used", www.2cto.com round (f. free/. total) * 100) "% Free" from (select tablespace_name, sum (bytes/(1024*1024) total

The protection level of Data Guard 10g is RESYNCHRONIZATION. After the data guard of Oracle is created, check the value of protection_mode and protection_level of v $ database. If the value of protection_mode is maximum availability, the value of

Import DMP to a different tablespace. 1. Use imp to export data. cmd to enter the orcle installation directory bin. Enter the following command: www.2cto.com exp username/password @ ORACLEEPP file = c: \ hysjb. dmp owner = magazine_hy rows = y 2,

Create or replace function gettaxcycle (www.2cto.com vv02 IN vv02_accounts_tin % ROWTYPE, returnoption in number) return number as tr12rec %% ROWTYPE; tg05rec %% ROWTYPE; taxcycle NUMBER; begin select * INTO tg05rec FROM tg05_tax_type_details WHERE

Common commands for Oracle to view table structures to obtain tables: www.2cto.com select table_name from user_tables; // select table_name from all_tables for the current user's table; // select table_name from dba_tables for all users; //

Using BCV to back up Oracle Database BCV (Business continuous Volume) is short for Business continuity Volume and the concept of EMC's product TimeFinder. It can be used for backup of massive databases and creation of Test Databases. One of the

Oracle I/O slave process www.2cto.com I/O slave process is used to simulate asynchronous I/O for systems or devices that do not support asynchronous I/O. for example, tape devices (relatively slow) do not support asynchronous I/O. by using an I/O

ORACLE sets the process priority in the operating system. We can use the renice command to set the process priority so that the process can obtain the CPU time slice first. In www.2cto.com ORACLE, the parameter _ high_priority_processes can also be

Oracle 10g obtains the result set of merging values in column B based on the same value in column a. oracle 10g obtains the same value according to Column, obtains the result set that combines values in column B. (Make a and B form a parent-child

Using rowid logic to extract data in parallel when we migrate or synchronize data, we often encounter oracle needs to read rollback segments for tables with frequent application changes, it may lead to a very slow process. Sometimes it may even

COL command:It mainly formats the display of columns.This command has the following options:COL [UMN] [{column | expr} [option...]The Option can be the following clause:Www.2cto.comALI [AS] aliasCLE [AR]FOLD_A [FTER]FOLD_ B [EFORE]FOR [MAT]

The UTL_FILE package of ORACLE UTL_FIle is used to read and write files in the operating system, provided that the Directory object and authorization are created first. Then you can use the types, procedures, and functions provided in the UTL_FILE

When SQL Server is used, an auto-increment field is added and set as the primary key to avoid repeated records. Now let go of the advantages and disadvantages of doing so. Let alone implementation problems. When Oracle is used, this situation occurs.

A bug of oracle-rdbms-server-11gR2-preinstall solved Oracle provides a very convenient Kernel Parameter Modification RPM package, indeed saves a lot of trouble, especially after the script, only need www.2cto.com cd/etc/yum. repo. d/wget

Sys @ ORCL> select recid, sequence # from v $ log_history; recid sequence # ---------- 1 1 2 2 3 3 4 4 5 5 6 6 7 8 8 9 9 10 11 11 12 12 13 1 14 2 15 3 16 4 17 1 18 2 19 3 20 4 21 5 22 6 23 7 24 8 25 9 26 10 27 11 28 12 29 13 30 14 31 15 32 16 33 17

Oracle restores accidentally deleted data table records. If no truncate statement exists, you can choose to recover the table records based on the transaction commit time. The general steps are as follows: www.2cto.com 1. First query from the