Oracle

The Enterprisedb database is compatible with postgresql during installation. The oracle-compatible method is changed to postgresql-based enterprise-level database. 1 www.2cto.com create a user named enterprisedb2 on the OS to create a new dataset

Oracle notes: Tables and fields (3) 4. change the field name, size, TYPE, and so on: Change the name: www.2cto.com alter table mytable rename (OLD_FIELD) TO (NEW_FIELD); size and TYPE: alter table mytable modify FIELD_NAME TYPE (LENGTH ); where:

As a DBA, the summary of oracle zone management and segment space management is one of the common scenarios: Creating tablespaces: www.2cto.com [SQL] create tablespace Think datafile '/u01/app/oracle/oradata/orcl/think. dbf 'size 100 M autoextend on

When parsing oracle rownum, I recently used oracle rownum for paging display, and made further analysis and research on rownum. This is summarized as follows, hoping to benefit everyone. For rownum, www.2cto.com is the number of the row returned

Oracle 11g the account is locked. Www.2cto.com 1. Failed to log on multiple times (the password may be incorrect); 2. the user is locked manually by the Administrator; 3. The user password expires, the password is not modified on time, and so on.

The first reason for this error is that the session and process connections are full. view the number of sessions and processes at www.2cto.com: select count (1) from v $ session; select count (1) from v $ process; display the maximum value of

Wm_concat instance row-to-column [SQL] www.2cto.com create table wlbtest1 (username varchar2 (2), deptID number); create table wlbtest2 (deptName varchar2 (10), deptID number ); insert into wlbtest1 values ('A', 1); insert into wlbtest1 values ('B',

Comparison between the round () function and trunc () function in Oracle round (x [, y]) www.2cto.com [function] returns the rounded value [parameter] x, y, numeric expression, if y is not an integer, the y integer is truncated. If y is greater than

How can we use the oracle keyword as the field name? What should we do when we define the field name and alias with the same name as the oracle keyword? In fact, it is very simple. Just add "", such as "group" www.2cto.com here to see the following

Introduction to parallel execution in Oracle 1. The concept of parallel execution is to physically divide a large serial task into several smaller parts, which can be processed simultaneously. This is like building a house. There are some things

Pay attention to the two ratio environments in the SQL Execution Plan: www.2cto.com [SQL] sys @ ORCL> select * from v $ version; BANNER -------------------------------------------------------------- Oracle Database 10g Enterprise Edition Release 10.2

Temporary tablespace group (TTG) environment for Oracle temporary tables: www.2cto.com [SQL] sys @ ORCL> select * from v $ version; BANNER implements Oracle Database 10g Enterprise Edition Release 10.2.0.1.0-Prod PL/SQL Release 10.2.0.1.0-Production

Oracle LAN connected to the database today is connected to the local area database, the problem can be said to be a variety of problems, so I want to share with you here, I am the first time to use the oracle database, so it is relatively unfamiliar,

Four methods of data block consistency check (I) What is data block consistency? Www.2cto.com each data block header has a "checksum" field. When the data block is written back to the disk, Oracle recalculates the checksum and records the field,

ORA-12514 listening error resolution error: [oracle @ prudentwoo admin] $ sqlplussystem/oracle @ PRUDENTWOOSQL * Plus: Release 11.2.0.1.0 Production onWed Dec 12 03:23:29 2012 Copyright (c) 1982,200 9, Oracle. all rights reserved. www.2cto.com ERROR:

Partition index causes database paging disorder select t2. * from (select t1. *, rownum rn from (select * from tb_courseinfo orderDatatime desc) t1 where rownum 100 www.2cto.com may be retrieved due to repeated datatime numbers. There are two

Special characters in SQL & processing update userinfo set pageurl = 'myjsp? Page = 1 & pagesize = 10 'where id = 'test' www.2cto.com? Two methods: 1) update userinfo set pageurl = 'myjsp? Page = 1' | '&' | 'pagesize = 10' where id = 'test' 2)

Generally, it is only used as a client to access Oracle and does not need to install a large Oracle database. Sometimes I often forget how to configure the lite version of Oracle. This article creates a record backup. You can download the client

Common oracle commands tnsping Oracle Net tool (command) tnsping is an OSI Session Layer tool used to: 1) Verify name resolution (name resolution, of course, it is oracle's own network service name) 2) whether the remote listener starts www.2cto.com

Create or replace function PARSE_FEE_CHINESE (n_0000in NUMBER) 002 RETURN VARCHAR2 AS003 V_CHINESE_NUMBER VARCHAR2 (30): = 'zero errors '; www.2cto.com 004 V_CHINESE_POINT VARCHAR2 (30): = 'round-Robin trillions of RMB '; 005 V_RESULT VARCHAR2 (100):