Database Administrator

This article uses seven simple steps to set the root password of the MySQL 5.0 database.Operating System: DEBIAN LinuxMySQL database version: 5.0.27(1) log on with the root permission of the system;(2) stop the MySQL server: MySQL. server stop;(3)

Operating System: SUSE Linux Enterprise Server 11 (i586)Database Version: Oracle 10.2.0.1Database Client Version: oracle10.2.0.1Introduction: in the company's recent phase II project construction, the newly purchased PC server needs to be deployed

MySQL 5.6 is coming soon, and 5.6 has made many optimizations to the optimizer. This time I mainly explain MRR (MULTI-RANGE-READ ). I used stored procedures to explain the changes in this process. Let's take a look. For statements:

A MySQL cluster is a technology that applies a memory database cluster in a SNA (Share Nothing Architecture) system. This non-shared architecture can make the system use low-cost hardware to obtain high scalability. A MySQL cluster is a distributed

Load Balance is one of the most important features of Oracle RAC. It distributes the Load evenly to each node in the cluster to improve the overall throughput of the system. Generally, there are two methods to achieve load balancing. One is Load

Create index idx_p_merchant_detail_id on D_ORDER_DETAIL (merchant_detail_id) Online; After the index is created for a long time, it is not reflected. Then, when the index is deleted, the following error is returned: Error: ORA-08104: this index

Instance and database startupShows the statuses from the last full shutdown to the startup of the database. When the database is started, it goes through three statuses: 1. Enable the instance (nomount)The instance is started but not associated

Backup is a top priority for DBAs. No matter how powerful your technology is and there is no backup, you are still helpless when something goes wrong. Here is just the BACKUP command summarized in the work. The scripts collected in the future will

In mysql-cluster, if you want to upgrade an SQL node to a Web server, you need to install php and php extension modules for mysql on the node, but there will be conflicts. The command to install php is: # php53 will install the dependency package by

How to automatically add the suffix. US. Oracle. COM when Dblink is created in ORACLE Step 1: view the global_name Parameter Obviously, the suffix automatically added is generated here. Step 2: log on to the database as a dba and modify the

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 protection_level should also be this value. If it is not the

Use filesperset to control the size of a backup set When the filesperset parameter is specified, rman compares filesperset with the automatically calculated value (for the number of files in each allocated channel) And take a smaller value to

I would like to summarize several other experiments on high-availability clusters. Let's look back at the content summarized by others. It's very fine, and a lot of content has been extended. Sorry, I just skipped it, haha ~~~ Here we will summarize

Expired Oracle user logon password Modification 1. Check the user's proifle, which is generally default: SQL> SELECT username, PROFILE FROM dba_users; 2. view the password validity period settings of the specified profile (such as default: SQL>

ORA-19870 and ORA-19573 errors, such: RMAN> restore database; Starting restore at 11-DEC-12Using channel ORA_DISK_1 Channel ORA_DISK_1: starting datafile backupset restoreChannel ORA_DISK_1: specifying datafile (s) to restore from backup

In this case, the root password of MySQL is lost. To restore it, let's talk about the environment first: Red Hat Enterprise Linux 6.3 x86_64 MySQL 5.5.28 According to your previous experience, modify my. cnf: Add skip-grant-tables in [mysqld],

In Oracle versions earlier than 11g, if you want to set the table to read-only, you can grant the SELECT object permission to these users, but the table owner still reads and writes the table. Oracle 11g allows the TABLE to be marked as read-only

Before Oracle 11g, we can create pfile from spfile or use pfile to create spfile. In Oracle 11g, spfile management is enhanced. You can use memory to create pfile and spfile. Syntax: Create pfile [= 'pfile _ name'] FROM {SPFILE [= 'spfile _ name']} |

1. DB_BLOCK_CHECKSUM parameter description Before Oracle 10.2.0.3: DB_BLOCK_CHECKSUM has two options: TRUE and FALSE. The default value is TRUE. In Oracle 10.2.0.3: DB_BLOCK_CHECKSUM has three options: OFF | TYPICAL | FULL. The default value is

This problem occurs when Oracle exp exports tables and data (when the 10g client is used to export 11g tables and data everywhere ); The solution is as follows: 1. Set the value of deferred_segment_creation to false. This method is only valid for