Oracle

Import Export using Exp/imp Before starting Exp/imp, there are several points to note: 1 This section takes Oracle 10g for example. 2 Exp, IMP is the next executable file of the operating system, stored in the/oracle_home/bin directory. So between

Let's take a brief note. Today, helping colleagues guide the data, from the development environment to the test environment, found that a query is slow. See the execution plan, and found that the full table scan (about 300w records in the table),

Preface: What can you learn through this study Directory: One, what is a trigger. second, what is the application scenario of the trigger. 1. Complex security Checks 2, the data confirmation 3. Realize audit function 4, the completion of data

In the query can not avoid the sorting, general write SQL we will add sort fields. If the sort field is a string, that's a bit of a hassle. For example, a number field should have been designed as an integer, but designed to be a varcher type.

Problem Description: Use Oracle's multiple page query statement, data duplication between different pages, but the database data is correct, query all the time can also be displayed. SQL instance: Select RowNum rn,ta.* from (select a.*,b.* to

My method source code: public boolean addtickets (Ticketsvo vo) {Boolean flag = false;Date in the corresponding databaseTimestamp stamp = Dateconventer.strwithtimetotimestamp (Vo.getbegintime ());Object[] Paramvalues={vo.getticketname (),

Set Autotrace off Set Autotrace on Set Autotrace traceonly Set Autotrace on explain Set Autotrace on statistics Set autotrace on explain statistics Set Autotrace traceonly explain Set Autotrace traceonly Statistics Set Autotrace Traceonly explain

In operatorThe advantage of using in-write SQL is that it is easier to write and understand, which is more suited to the style of modern software development. However, in SQL performance is always lower, the steps that are performed from Oracle

When using Oracle for paging queries, we typically carry a lot of parameters. But today I found a very strange thing, when the sort field is not a primary key, and the value of the sorted field in multiple data is the same, the sort order of the

Query and delete duplicate records SQL statement 1, find redundant records in the table, duplicate records are based on a single field (ID) to determine select * from table where Id in (select Id from table group Byid having count (ID) > 1) 2,

Oracle redo logs Oracle 's database log is called Redo log, and all data changes are recorded redo log, which can be used to repair a damaged database. The redo log is grouped, and the default is three groups. Redo Log is used in turn, a redo log

It is possible that the current number of connections on the database has exceeded the maximum value that it can handle.Select COUNT (*) from v$process--current number of connectionsSelect value from v$parameter where name = ' processes '--maximum

Oracle generates 1 million test data in the following ways: Method One: Create a table, add 1 million data at the same time, code: CREATE TABLE TestTable as select RowNum as ID, to_char (sysdate + rownum/24/3600, ' yyyy-mm-dd

In today's ATM, the data is processed using pure JDBC, and when it is discovered that the relationship between user and Card,log is used, the field in the card is associated with the ID in user, and the number of inserted and updated rows that are

Workaround: 1. View database lock, diagnose the source and type of lock :　　 Select Object_id,session_id,locked_mode from V$locked_object; or use the following command: Select B.owner,b.object_name,l.session_id,l.locked_mode From V$locked_object

1. Add the log file to be parsed EXECUTE DBMS_LOGMNR. Add_logfile (-logfilename => '/home/duanbb/oracle/oradata/mydb/redo01.log ',-OPTIONS => DBMS_LOGMNR. NEW); EXECUTE DBMS_LOGMNR. Add_logfile (-logfilename =>

Restore Segment Purpose:Transaction fallback--when a transaction modifies a row in a table, the old image of the modified column (the data to be restored) is stored in the restore segment. If the transaction is rolled back, the Oracle server

Connect Resource Permission Grant Connect,resource to user; Permissions that the user includes after executing the above SQL statement: Connect Role:--is the typical right to give end users, the most basic Alter session--modifying sessions Create

The original source of this article: Http://blog.csdn.net/tianlesoftware/archive/2009/10/23/4717318.aspx There are 4 ways to convert plain tables into partitioned tables : 1. Export/import method 2. Insert with a subquery method 3. Partition

Oracle Start listening Service Lsnrctl start Stop the Listening service Lsnrctl stop Ora-12514:tns: The listener is currently unable to recognize the service requested in the connection descriptor Need to configure Listener.ora files in Oracle