Database Administrator

A profile has dual function: toenforce a password policy and to restrict the resources a session can consume; Password Management is always effective It is valid only when the initialization parameter RESOURCE_LIMIT is TRUE for resource management.

Read consistency ensures that the query results are consistent with the data at the time when the query is initiated, regardless of whether other transactions have changed the data during the query. Assume that we have the following function to

DBMS_OUTPUT has the upper limit of the cache. The default value is 10000 bytes. When the value exceeds 10000, an exception "buffer overflow, limit of 10000 bytes" is thrown. Test the stored procedure as follows: Create or replace procedure

The execution speed of SQL statements may vary depending on many factors. However, the main influencing factors are: driving the table, executing the operation sequence, and applying the index. These factors can be indirectly changed by many

Add reference: Using System. Data. OracleClient; Here I select an Oracle (Service name (Data Source here is separated from Data Source): GIS user Name (user): gis password (password): gis) your Oracle database has its own name. Please modify it. I

The following describes how to add a disk to an Oracle ASM disk on the Linux platform. 1. Operating System settings 1. Map the storage disk to the server, restart and scan the disk. /Opt/D */bin/dlnkmgr view-lu 2. After scanning a new disk (both

Use log mining to restore accidentally deleted tables, data, and views from incomplete Oracle recovery /*-------------------------- Prerequisites: 1. DB works in archive mode; 2. Prepare cold data files; ---------------------------*/   Col

I. Description There are three types of SCN in a data block of Oracle, namely the block header SCN, CSC (cleanout SCN) and commit SCN in ITL. You can dump the block to view the specific information in the block. This is organized in my previous blog:

Statspack is a powerful and free performance analysis tool provided by Oracle. Use a user with sysdba permissions to log on and install the SDK. With Statspack, we can easily identify the bottleneck of the Oracle database, record the database

Background: The PostgreSQL server runs on RedHat Linux and the IP address is 192.168.230.128. The client is installed on Windows XP with the IP address 192.168.230.1 Configuration method: 1. Modify the/opt/postgresql/data/postgresql. conf file on

By installing rac 10g for RedHat as 4 and rac 10g for redhat as 5, it is found that the self-starting configuration of bare devices is different. The configurations of the two versions are listed below 1. linux redhat as 4 Edit

Logical Storage Structure The file corresponding to the logical storage structure cannot be found in the operating system, but the description of the logical storage structure can be found by querying the data dictionary of the Oracle database. The

How does Mysql implement MVCC? There are countless people asking this question, but there is no answer in google. This article attempts to find the answer from the Mysql source code. In Mysql, MVCC is supported in the Innodb Storage engine. Innodb

-- Obtain the SQL Execution Plan and statistics without displaying Query InformationSQL> set autotrace traceonly;SQL> select * from test;Execution Plan----------------------------------------------------------Plan hash value: 1357081020--------------

Oracle said that, according to internal standards, on Linux, the read/write speed of MySQL 5.5 is 5.1 higher than that of MySQL 360%. On Windows Server, the performance has been improved by more than 1500%. And our Discuz! And Discuz! The X series

Errors that occur when a user is authorized: # Sqlplus/as sysdba SQL> grant sysdba to sys_user_admin;Grant sysdba to sys_user_admin * ERROR at line 1: ORA-01994: GRANT failed: password file missing or disabled SQL> show parameters pass NAME TYPE

Copy patch filesThe patch number for Oracle11.1.0.7.3 is 9352179, and 9776431 is a problem patch Based on 11.1.0.7.3. Copy the patch file to/opt/orabak. The directory structure is as

The following is an example and description of creating an auto-incrementing sequence for a field in an Oracle table. /* ===================================================== ======================================= *//* Set auto-increment sequence:

Starting to test Oracle 11g rac, the current performance is limited, so a single node rac is installed. The procedure is as follows: Modify ifcfg-bond * ifcfg-eth * in/etc/modprobe. conf and/etc/sysconfig/network-scripts by binding the NIC * I will

Upgrade a single Oracle 11.2.0.1 instance to 11.2.0.3. Oracle upgrades are similar. Upgrade Oracle software and then Oracle instance. The patchset No of Oracle 11.2.0.2 is 10098816. For details about this Patchset, refer to the following