first, log in to the database, create the table User00 in the database, and insert the data .
The fields of the table are:
Id (number), name (name), Grid (level), Score (integral), Password (password), age (Ages), Code (invitation code). (where
Data Guard offers two main services:1 Redo Transport Service: The Primay end of the redo log transmission to one or more standby destinations.2 Redo Application Service: The redo log which is transmitted from the Primay end is applied to the standby
Oracle CPU is too high to handle, this article will describe the Oracle process CPU usage is too high, need to know more than friends can refer to the
1: First use the top command to upload the CPU-intensive SPID number
PID USERNAME THR PRI Nice
If there is a lock waiting, we might be more interested in knowing who locked the table and who's waiting.The following statement can query who locked the table:
Copy Code code as follows:
SELECT/*+ Rule * * s.username,
Decode
I have a strange question today:Use Sqlplus on the client to log on as a normal user, but neither system nor SYS users can log on, prompting Ora-12154:tns: Unable to resolve the specified connection identifierSql> Conn System@webdataEnter
Meaning explanation:
Decode (condition, value 1, return value 1, value 2, return value 2,... Value N, return value N, default value)
The meaning of the function is as follows:IF condition = value 1 THENreturn (translation value 1)elsif condition =
?
Class Db_sql {
var $Debug = false;
var $Home = "/u01/app/oracle/product/8.0.4";
var $Remote = 1;
/* This Query is sent directly after the ' the '
Example:
var $ConnectQuery = "ALTER session SET Nls_date_language=german nls_date_format= ' DD." Mm.
1. The case-when expression has two forms
Copy Code code as follows:
--Simple Case function
Case Sex
When ' 1 ' THEN ' male '
When ' 2 ' THEN ' woman '
Else ' other ' end
--case search function
Case
When sex = ' 1 ' THEN
ORACLE EBS operates on a form interface, or when a background database operates on a table, it is found to be "suspended animation", possibly because the table is locked by a user, causing other users to fail to continue
Copy Code code as
At the end of last year did a lot of system data migration, most of the system due to platform and version of the reasons, do is a logical migration, a small part to do is physical migration, some experience, and share with you.
First of
Scott user's password is not correct, enter administrator user, modify Scott user password can
or modify the password like this:
In the Run Bar Knock: Sqlplus (space)/nolog carriage return
Then knock in the pop-up box: Conn Sys/password as SYSDBA
1: When multiple table associations are used, the multiple where statement minimizes the result set of a single table, uses aggregate functions to summarize the result set, and then associates with other tables to minimize the amount of result set
Forget the login password for users other than SYS and system users.
Log on with the SYS (or system) user.
CONN Sys/pass_word as SYSDBA;
Use the following statement to modify the user's password.
ALTER USER user_name identified by Newpass;
Note:
The operation of the database is one of the necessary development parts of the current system development, especially in the large data age, the database is especially important. But do you really understand how Java and the database are connected?
1. Group function Usage Rules
Group functions in MySQL can be used at will in a SELECT statement, but in Oracle if there is a group function in the query, the other column names must be processed by the group function, or the column in the GROUP BY
The most basic Oracle database connection code (for oracle11g only):
1, right key project-> build path-> Configuration build path, select the third "library", then click "Add External Jar", select "D:\Oracle\app\oracle\product\11.2.0\server
To build an Oracle, there will be many schemas below, and no data under each schema is affected.
Feel and MySQL library concept is very similar, now use the database management system is in fact so divided, MySQL with the ip+port+ library
--View Current User select Username from dba_users;--Creating a temporary create USER GZMPC identified by PASSWORD;--authorizing Grant CREATE SESSION to GZMPC; CREATE tablespace gzmoc_wk datafile'Gzmoc_wk.dat'SIZE 10M autoextend on; CREATE temporary
E:\>exp help=y By entering the EXP command and username/password, you canCommands after the user/password: Example: EXP Scott/tiger Alternatively, you can control how export runs by entering an EXP command with various parameters.To specify
The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion;
products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the
content of the page makes you feel confusing, please write us an email, we will handle the problem
within 5 days after receiving your email.
If you find any instances of plagiarism from the community, please send an email to:
info-contact@alibabacloud.com
and provide relevant evidence. A staff member will contact you within 5 working days.
A Free Trial That Lets You Build Big!
Start building with 50+ products and up to 12 months usage for Elastic Compute Service