Oracle

Oracle Database defragmentation table Fragmentation reprint: Source of http://kyle.xlau.org/posts/table-fragmentation.html table fragmentsWhen there are many deletions for a table, the table generates a lot of fragmentation. The space freed by the

Oracle initialization or shutdown in progress this error message when you log in to Oracle today, searching the web, trying a lot of ways, and finally combining several methods to successfully solve the problem! cause : I mistakenly delete a

Before Oracle 11g it was a bit of a hassle, after 11g, it was very simple. Now has the function business is, has a test table records is the document approval information, the ID is the approval information primary key, SHEET_ID is the foreign key,

I. Naming rules for table names and columns1, must start with a letter. 2, the length can not exceed the characters. 3. You cannot use Oracle 's reserved words. 4, can only use the following characters a -Z, a-Z,0-9,$, # and so on. Ii. data types

The first thing to know about Undo is that undo is a very useful feature in OracleThe undo data is also known as rollback (ROLLBACK) data, which is used to ensure consistency of data. When a DML operation is performed, the data before the

Find the top 10 poor performance SQL.SELECT * from (SelectfromorderbyDESC ) where ROWNUMView a running session with a large IOSELECTSE.SID,SE.SERIAL#,PR. Spid,se.username,se.status, Se.terminal,se.program,se. Module,se.sql_address,st.event,st.

Time synchronization between nodes is important for Oracle and is often done by setting up an NTP server before the 11g release. In Oracle 11g, a new CTSS (Cluster time Synchronization Services, cluster synchronization Service) service was added to

In order to further the left outer connection, we do some tests, and the outer joins are written in several forms, and we can trace to the final SQL conversion form by 10053.--Initialize dataCREATE TABLE A(ID number,Age Number);CREATE TABLE B(ID

1after installing the Oracle database: Execute Dbstart and Dbshut will prompt: [[email protected]~]$ Dbstartoracle_home_listner is isn't SET, unable to auto-start Oracle Net listenerusage:/u01/app/oracle/oracle/product/10.2.0/db_1/bin/Dbstart oracle_

Syntax: drop table ... purge; example: Drop table Test Purge;purge is deleted directly from tables, not reserved to Recycle Bin, 10G start default drop table name change to recycle Bin; Flash back (Flashback) statement: 1, Can restore a table to a

We can use the Oracle Audit function to record user login information, but if opening the Audit function will degrade Oracle performance and even cause Oracle to crash. So how can we record user login information? We can actually do this by creating

Exchange Partition provides a way for you to migrate data between a table and a table or partition and partition, noting that the table is not converted to a constituent or non-partitioned form, but only to the number of migrated tablesIt is the

1. First create a table to hold the error message 12345678 CREATETABLE TBL_PROC_ERRMSG(  BIZ_CODE VARCHAR2(50),  ERR_LINE VARCHAR2(10),  ERR_CODE VARCHAR2(10),  MSG VARCHAR2(200),  CRT_TM   DATE DEFAULTSYSDATE); 2.

It was suddenly discovered today that the "not equal to operator" in Oracle ignores null.For example, query comm is not equal to 300 of the records, I will take it for granted where comm! = 300It is expected to return a record that contains null

Tkprof is a command-line tool provided by Oracle, the primary role is to convert the original trace file to a formatted text file, the simplest way to use the following:Tkprof LY_ORA_128636.TRC Ly_ora_128636.txtTkprof has many parameters, and in

The concept of a transaction:Transaction: A transaction consists of a set of DML statements that make up a logical operationThe transaction begins with an end, and the transaction begins with a DML statement, ending with conmmit and rollback.The

Under Oracle 10g, the dependency is judged to be at the object level, which means that once the object accessed by the stored procedure has changed, Oracle will place the stored procedure in the invalid state. So after the DDL operation for the

How to check whether the SQL statements are correct when executing large SQL statements in Oracle stored procedures? A large SQL statement is sometimes used in the preparation of a stored procedure in Oracle. However, you cannot see the SQL

Share: Oracle System Variable Function usage instructions, oracle VariablesIn Oracle databases, Oracle System variable functions are frequently used. Let's share the usage of Oracle System variable functions. Oracle functions are diverse. System

New Features of Oracle11g: invisibleindex (invisible index) How do you feel if a table has more than a dozen indexes? Obviously, it will slow down the process of adding, deleting, and modifying data. Do not expect developers to build indexes. My