Database Administrator

-- Monitor whether the index is used Alter index & index_name monitoring usage; Alter index & index_name nomonitoring usage; Select * from v $ object_usage where index_name = & index_name; -- Calculate the I/O distribution of data files Select df.

It is easier to install MySQL in Solaris than to install Oracle. The following describes how to install MySQL in Solaris. Operating System: Solaris10Database: mysql5 Mysql-5.1.42-solaris10-i386.pkg.gz 1. Transfer media to the server I use FTP to

We all know that date and timestamp are both expressions of date and time, but the two types of precision are different. The former is accurate to seconds, and the latter is precise to decimal seconds (fractional_seconds_precision ), it can be 0 to 9

Logging always assumes that the log of a table is set to NO and it will not generate logs. In fact, the following is not an explanation and experiment of logging. Logging Introduction You can perform the following operations in nologging mode: 1.

The day before yesterday, the customer called and said that the background database of the GPS inspection system had crashed because the space allocated to the image storage disk was insufficient and he adjusted the partition. I asked him to back up

Recently, when performing some partition operations in Oracle, the global index of some partition tables is always invalid. Therefore, perform a detailed test on the related operations. The following is a summary of my test results: ADD partition,

I just tested a program and reported an error saying that the data was not found: Rochelle date1! = L_date2L_date1 = 26-MAY-11, l_date2 = 26-MAY-11 ...... It turns out that it was nls_date_format. Oracle uses built-in programs such as

We all know that Latch is the mechanism that Oracle uses for serial control in memory. From 10g R2, Oracle introduced a new technology-Mutex. Mutex is not an invention of Oracle, but an underlying call provided by the system. Oracle only uses it to

When importing data in half, the disk space is insufficient. This requires that the data of the database files be moved to another disk. 1. offline data files: SQL> alter database datafile 2 'H: \ Oracle \ product \ 10.2.0 \ oradata \ lhoms \ pub \

NEXT_DAY (date, char): returns the date of the first day of the week (specified by char) after the specified date (specified by date). char can also be 1 ~ Replace 7. 1 indicates Sunday. Duzz $ scott @ orcl>SelectSysdate, to_char (sysdate,'Day')

Summary of several methods for disabling and starting Oracle:There are several startup methods:1. startup nomountNon-installation startup. In this mode, you can execute: re-build the control file and re-build the database. Read the init. ora file

Add a mysql user group and a mysql userGroupadd mysqlUseradd-g mysqlPasswd-u mysql 1. Install the required software packageYum install gcc-c ++ libtool autoconf automake imake libxml2-devel expat-develYum install ncurses-devel makeYum install

Source code: xx. pc /*  Function: demonstrates Oracle non-scroll cursor operations    Considerations when defining a cursor:  1. The declare cursor statement must be the first statement to use the CURSOR.  2. The cursor name is an identifier

I. Environment Introduction IP_Address Port_No Node_name Service_name Desc 192.168.56.101 3306 SQL node) Mysqld SQL node (API node) 192.168.56.101 2202 Data Node Ndbd Data Node 1

Grant the user a connect role and a resource role: Grant connect, resource to user; Permissions granted to the user after successful running: CONNECT role: -- is the most basic and typical right granted to end users. Alter session -- modify a

1. Introduction to Oracle dml SQL rollback LogicDatabase transactions consist of one or more DML (insert, update, delete) SQL statements. We know that the Oracle database uses the UNDO tablespace to store transaction rollback information during DML

Recently, due to system cleanup, the optimizer accidentally deleted oralce's log file, and Oracle reported ORA-00313 and ORA-00312 errors when the result was started. Run the following command in "run": sqlplusw/nologSQL> conn/as

[This article only records the upgrade process, does not discuss the advantages and disadvantages of the two versions, and the current database on this website is relatively simple, there is no stored procedure or anything, so the same method cannot

Because MySQL currently does not support dynamic parameter paging, you can either pass the SQL statement in the stored procedure or write a string connection method by yourself. Method 2 Write one line for each place to be split and clear BEGIN

Generally, it is easier for a database to obtain the dbid through mount. C: \ Users \ Liangwei> rman target/ Recovery MANAGER: Release 10.2.0.3.0-Production on Friday Aug 17 21:29:05 2011 Copyright (c) 1982,200 5, Oracle. All rights