Oracle

--First part: SQL Basic--ch1 Simple Query--CH2 query basic concept--CH3 data filtering--Part Two: Multi-table Operation--CH4 set theory--ch5 inner Connection--CH6 outer connection--ch7 subquery--Part three: Data grouping --ch8 Simple Statistics--CH9

：Http://www.oracle.com/technetwork/cn/articles/112010-win64soft-094461.html#* Special Instructions *#关于下载工具的使用: Do not use thunder download, at least I use the QQ whirlwind download two compressed folders within the folder merge does not appear to

Overview of basic methods for Oracle performance optimization1) Set up a reasonable performance optimization target. 2) measure and record current performance. 3) Determine the current Oracle performance bottleneck (what Oracle waits for and what

In recent days, I am responsible for the P project environment to provide a view of the W system, due to complex query logic, data volume is large, resulting in each query view time, query slow, inefficient, by the W system personnel complaints.

1 viewing SIDs$ echo $ORACLE _sidOrcl$ echo $ORACLE _home/u01/app/oracle/product/11g$ echo $ORACLE _base/u01/app/oracle$ mkdir-p/U01/ORADATA/ORCL$ mkdir-p/u01/app/oracle/admin/orcl/adump$ mkdir-p/u01/app/oracle/diag/rdbms/orcl/orcl/cdump$ mkdir-p/u01

A transaction is a logical unit of work that is used to cut database activity, where a transaction has a starting point and an end point;when one of the following events occurs, the transaction begins: Connect to the database and run the

A trigger is a special type of subroutine that resides in a database. cannot be called directly by the user, but is initiated by the system when a particular event or action occursTune with the holder line. The trigger cannot accept the number of

The System (Oracle+weblogic) released in the previous period frequently hangs, every morning 9 points, 2 o'clock in the afternoon peak on the hanging, tangled for a long time, the final Solution, method description under.Executes select COUNT (*),

ORACLE SQL TraceAUTOTRACE command1 SET AUTOTRACE off this is the default value, which is to turn off AUTOTRACE2 set AUTOTRACE on produces a result set and interprets the plan and lists the statistics3 Set AUTOTRACE on EXPLAIN display result set and

Import java.sql.Connection;Import Java.sql.ResultSet;Import java.sql.SQLException;Import java.sql.Statement;Import java.sql.PreparedStatement;public class lx02{public static void Main (string[] args) throws SQLException, classnotfoundexception{Load

Reprint: Source http://www.2cto.com/database/201209/154722.htmlTo set the Oracle PL/SQL Time display format Nls_timestamp_format the display format of TIMESTAMP time in Oracle Oracle database Time field We usually use the TIMESTAMP format, before

In Oracle, sequence is the so-called serial number, each time it takes its own initiative to add, usually in order to be ordered by serial number place.1. Create SequenceYou first have to have create sequence or create any sequence

/*************************************************First, the topic: ORACLE try not to use an implicit conversionTwo ways to type conversions: Display type conversion (EXPLICIT) automatic type conversion (implicit)*************************************

 1 start and end time of the fetch week The start time of the week is taken, beginning with Monday. Sql>select TRUNC (to_date (' 2013-11-25 10:31:11 ', ' yyyy-mm-dd HH24:MI:SS '), ' D ') + 1 ASA from DUAL;A-----------2013/11/25

Let's talk about the ORACLECPROCD process. List knowledge points about oprocd Oprocd is introduced by oracle in rac for fencing io In unix systems, if we do not use third-party cluster software other than oracle, The oprocd process will exist. In

1. If you have a plsql client, you can use this user to log on and right-click all tables and Drop them.2. If you have the permission to delete a user, you can: Drop user user_name cascade; With cascade, you can delete all associated user data.

In oracle, there are rank, dense_rank, row_number, and group ranking partition. Note: RankDense_rankRow_number: the ranking adopts a unique sequence number continuous value, for example, 1, 2, 4Partition: Limit the ranking to a

This error is often returned when an Oracle database is shut down illegally: EXP-00056: ORACLE error 1033 ORA-01033: ORACLE initialization or shutdown in progress User: password: This is obviously because the database cannot be started, but the

[Cause/trigger factor] This is because "PASSWORD_LIFE_TIME = 180 days" is set in the default profile in oracle11g by default. [Impact and risk] Impact After the password expires, the business process has an exception connecting to the database,

Golden Gate (OGG for short) provides real-time capturing, conversion, and delivery of transaction data in heterogeneous environments. OGG supports the following heterogeneous environments: OGG features: Small impact on the production system: reads