Database Administrator

Installing Oracle 10 Gb in CentOS 4.6 may cause the following common errors: The preceding error indicates that the Display variable of the X11 Window Server is incorrectly configured. Solution: open a terminal as root and enter "# xhost +" and "#

Find this article, which mentions MySQL encoding conversion from latin1 to UTF8. Add to favorites. Recently, all the databases will be transferred once, And latin1 is always incorrect. It will be too much trouble if it is not transferred. SET

Suppose we have the following table: Reference Id username password-----------------------------------1 admin *************2 sameer *************3. stewart ************* Create table if not exists 'admin '('Id' int (6) unsigned not null

Oracle locks can be divided into several types: DML lock (data lock), DDL lock (dictionary lock) and internal lock/latch.DML lock can be divided into row lock and table lock. Row lock in select .. for update/insert/update/delete is automatically

A few days ago, when the database space was full, it had increased to a maximum of 32 GB for a single storage file. However, a lot of methods are used to release the tablespace. The main reason is that the system uses a large number of partition

1. A table field in Oracle is of the Date type. The error message "Incorrect format" is always returned when you insert data into the file. Solutions: 1. Temporary Modification SQL> alter session set nls_date_format = 'yyyymmdd '; This method

I. Software PackagesA) sqlite-autoconf-3070400.tar.gz Ii. Installation Steps A) tar zxvf sqlite-autoconf-3070400.tar.gz B) cd sqlite-autoconf-3070400 C)./configure -- prefix =/usr/local/sqlite D) Make E) Make install Iii. SQLite3

To explain, the constraint test is delayed until the execution of COMMIT. The following are specific explanations and examples. The constraint defined as deferrable can be specified: 1. initially immediate (Initialization is executed immediately)

With the query syntax unique to Oracle, you can get twice the result with half the effort. As follows: 1. Tree Query Create table tree (Id number (10) not null primary key,Name varchar2 (100) not null,Super number (10) not null // 0 is root);-- From

1 Swingbench 1.1 Overview This was developed by an Oracle UK employee on the basis of a abandoned project. The current stable version is 2.2, the latest version is 2.3, based on JDK1.5. This tool is free of charge and can be freely downloaded from

Before Oracle 11g, the alter file of oracle was under the bdump directory. Oracle 11g provides Alert logs in XML and traditional text formats. The location of the new oracle 11g log is determined by the Automatic Diagnostic Respository (ADR. You

1. Download the binary version. Many websites now have related downloads, which are about 384 Mb in size and about MB in decompression. My downloaded version is: mysql-5.1.45-linux-i686-glibc23 2. The glibc2.3 version is required from the file name.

When using a data pump to export data, sometimes we need to filter out some data that does not need to be exported according to the conditions. In this case, we need to use the parameter query. The following is a small example of simple query. In

I believe everyone is very familiar with the index structure. It is composed of roots, branches, and leaves. Of course, this refers to the common B + tree indexes. We still use the test table in Oracle collection table and column statistics (see.

RMAN Fault Diagnosis script setNote:This script is used to collect RMAN information.This script is executed in RMAN. If RMAN CataLog is used, you need to use RMAN to connect to the database CataLog.This script will generate a script file

In Oracle, columns in the table below the sys user cannot be dropped. If drop is performed, an error is returned: SQL> desc test Name Null? Type ----------------------------------------------------------------------------- Id notnull number

1. Check whether the rpm is completeRpm-q -- qf "% {name}-% {version}-% {arch} \ n" binutils compat-libcap1 compat-libstdc ++-33 compat-libstdc ++-33. i686 elfutils-libelf-devel gcc-c ++ glibc. i686 glibc-common glibc-devel glibc-devel.i686

When we were hired to monitor MySQL performance, people wanted us to check MySQL configurations and give some suggestions for improvement. Many people are surprised afterwards, because we suggest that they modify only a few settings, even if there

After Fedora 19, Fedora replaces mysql with mariadb. Although these two things are the same, I still like mysql, and I don't know why. In Fedora 20 (64bit), I only installed mariadb once, no solution can be found on the Internet. (If anyone knows,

1. log on to the ASM instance and check whether the ASM disk is correct.[Oracle @ rhel5 ~] $ Export ORACLE_SID = + ASM[Oracle @ rhel5 ~] $ Sqlplus/as sysdbaSQL> select name, state from v $ asm_diskgroup; NAME STATE--------------------------DG1