Database Administrator

Oracle 10 Gb provides a way to use external tables to extract data. First, you need a directory (here we will continue to use the previously created directory) SQL> showUser USERIs"SYS" SQL>Select*FromDba_directoriesWhereDIRECTORY_NAMELike '%

There are also a lot of articles about OTL on the Internet, but it seems that it is only official documents. OTL is very easy to use. Combined with some official examples, you can try more to understand it. After about a month of project development,

First, you must first have the Python MySQL connection module MySQLdbIt has been installed by default in CentOS 5.4, but not in Ubuntu. You need to manually install it as follows: : Http://sourceforge.net/projects/mysql-python/ An example that can

How to improve query efficiency using Oracle statements1:... where column in (select * from... where ...);2:... where exists (select 'x' from... where ...);The second format is far more efficient than the first one. IN Oracle, almost all IN operator

By default, access between different Oracle Server databases is remotely accessed through local operations *. * 1. Create a database linkExample:Create public database link orcl211 connect to username identified by password using '(DESCRIPTION

Stored Procedures, functions, triggers, tables, etc. In PL/SQL: Export: Tool --> Export user object --> select multiple user objects to be exported, and select the path of the output script file (SQL file) --> export. A. SQL script file is

When Oracle 10g is installed in Linux and EM is enabled, garbled buttons are displayed as follows: I found the reason on the Internet. It turns out that when Oracle is installed for 10 Gb, JDK/JRE automatically selects the character set, in the $

PRAGMA is a Compilation instruction (or command ). Compilation instructions are processed during compilation. They are not executed at runtime. Compilation instructions are special commands issued to the Compilation Program. It is also called a

1. Main technologies used:Lucene 2.3.1IK_CAnalyzer 1.4 Chinese Word SegmentationHtmlParser 1.6 HTML file/Text parser disadvantage: cannot ignore Content 2. Other implementation methods: Perform incremental index content for each category every day:

104 scp to 25Scp/opt/Oracle/111/dbs/initORCL. ora root@10.1.0.25:/opt/oracle/111/dbs/initORCL. oraScp/opt/oracle/111/dbs/spfileORCL. ora root@10.1.0.25:/opt/oracle/111/dbs/spfileORCL. oraScp/opt/oracle/111/dbs/orapwORCL root@10.1.0.25:/opt/oracle/111

1. Introduction The full-text index plug-in is used to expand the full-text retrieval feature of MYISAM. Through full-text search, we can perform word segmentation on documents, images, videos, and other data types to create an index for quick

After compiling and installing MySQL, you can use gdb to track the execution of the mysql server. Gdb -- args/usr/local/mysql/libexec/mysqld (Gdb) B mysql_selectBreakpoint 1 at 0x8228b7d: file SQL _select.cc, line 2315.(Gdb) B my_net_readBreakpoint 2

Single-record functions in SQL 1. ASCIIReturns the decimal number corresponding to the specified character;SQL> Select Ascii ('A') A, Ascii ('A') A, Ascii ('0') Zero, Ascii ('') Space From Dual;A ZERO SPACE------------------------------------65 97 48

Note: This article is not to give you a case, but to explain the optimization method. The Ancients cloud: it is better to teach people to fish than to teach people to fish. Here we will talk about how to fish. The SQL optimization mentioned here is

Recently, Oracle 11g exp command was used to back up the database and restore the database. It was found that the table that has never inserted data before the export was not exported. Similar problems have not been found before when I was using 9i

Hibernate is a persistence layer framework that does not rely on any container and supports ing objects to database tables, ORM. Supports addition, deletion, modification, and query operations during development and encapsulates basic JDBC

By default, hr users and tables are not created. You can create a table by using dbca or script. Now I create hr users and tables in script Mode 1. Obtain the hr user script from the Internet 2. Add the script to the $

1. In the http://www.oracle.com/technetwork/database/index.html, enter the Instant Client for Linux x86 page, Then download the following installation package (10 Gb client, 11 GB latest

1. Check the character set when the Oracle database is created:Oracle Server executionSQL> select name, value $ from sys. props $ where name like 'nls % ';Name value $----------------------------------------------------------------------NLS_LANGUAGE

Oracle temporary tablespace is mainly used to query and store some buffer data. Temporary tablespace consumption is mainly caused by sorting the intermediate query results. The temporary tablespace can be released when the database is restarted. If