Oracle

--view disk statements that consume the most disk read and write rates Select * from(SelectV.sql_id,v.child_number,v.sql_text,v.elapsed_time,v.cpu_time,v.disk_reads,rank () Over(Order byV.disk_readsdesc) Elapsed_rank fromV$sql v) awhereElapsed_rank

1 SelectA.accountcodeid, A.accountcode, A.accountcodename,2Sys_connect_by_path (A.accountcodename,'\') asFullName, A.parentcodeid, Level3 fromFm_accountcode a4 whereA.accountcodeid>= 100005Start withA.parentcodeid is NULL6Connect byPrior

Oracle 11G R2Instance 1:192.168.1.211 Instance Name: FengInstance 2:192.168.1.212 Instance Name: WanNow in instance 2, do Dblink, query instance 1 above the dataOracle Administrator user system and password for instance 1 OracleModify on instance 2

1. ClassificationSeveral types of log files in Oracle Redo log files–> Online redo log Archive Log files–> Archive logs Alert Log files–> Alarm logs Trace files–> trace log User_dump_dest–> User trace log

Create a dictionary-managed tablespacecreate tablespace james datafile ‘/opt/oradata/orcl/james01.dbf‘ size 50 M, ‘/opt/oradata/orcl/james02.dbf‘ size 50 M minimum extent 50k extent management dictionary default storage (initial

InstallationFor installation Environment Select 2008R2, Memory 2G or more. Install path Select Plain English path.Installing the ServerInstall ClientInstall additional development tools (PL/SQL)UnloadingTurn off the appropriate service (restart

Introduction to LONGRAWBLOBCLOB type in Oracle Note: RAW: unprocessed type, which can store binary data or byte charactersLONG: variable-length string data. The maximum length is 2 GB. LONG has the VARCHAR2 column feature. It can store at most one

Oracle uses parallel pitfalls How can we quickly delete tens of millions of data records from tables with 10 million data records? You cannot directly delete the file. The best method is: 1. Use create table 2. Concurrent primary key and index

Use ORACLE online redefinition to change a common table to a partitioned table1. First create a test table and insert the test data: create table myPartition(id number,code varchar2(5),identifier varchar2(20));insert into myPartition values(1,'01','0

JAVA queries the Oracle database and exports it to txt text Import java. io. fileOutputStream; import java. io. printStream; import java. SQL. statement; import java. SQL. connection; import java. SQL. driverManager; import java. SQL. resultSet;

ORACLE Stored Procedure Prelude: 1: A Necessary concept: ORACLE provides the ability to store PL/SQL programs in databases and run them anywhere. In this way, stored procedures or functions are called. Procedures and functions are collectively

Operations for warehouse devices under mongolerman The database or VTL is used as the backup of key services. Although there is little contact with common users, the overall usage is still relatively large. Many instances use the disk mode to

Chinese conditions cannot be queried in oracle However, the following statement cannot find records with Chinese characters: Select drdl01 from prodctl. F0005 where trim (drdl01) like 'China, China % '; View the current database character set:

Use the transaction processing mechanism of Oracle Database in java code   // Use the java code to operate the oracle database: Package Transaction; import java. SQL. connection; import java. SQL. driverManager; import java. SQL. resultSet; import

How to create virtual columns and composite triggers for Oracle Data, oracle triggers This article describes the knowledge of virtual columns and composite triggers in Oracle databases, including the creation of virtual columns and composite

Common oracle Stored Procedure skills (details) and oracle Stored Procedure skills What we deal with most during pl/SQL programming is the stored procedure. The structure of the stored procedure is very simple. In addition to the basic structure of

Oracle grouping and sorting functions In project development, we sometimes encounter the situation that requires grouping and sorting to solve the problem:1. It is required that field1 be grouped and sorted by field2 in each group;2. It is also

Oracle sorting, oracle 1. Processing of NULL in ORDER By default, Oracle considers null as the maximum value in Order by. Therefore, if it is ASC, it is placed at the end of the ascending Order, and DESC is placed at the top of the descending Order.

The number of tablespaces configured in Oracle increases and the number of tablespaces in oracle increases.Oracle alter tablespace size After using Oracle10g to create a database, some data is imported into the database. An error occurs when you

Oracle Data Pump, oracle   To use the data pump, you must first create a database directory Database directory only allows sysCreate Common usersAuthorization required Assume scottThe user is an import user. SQL>! Mkdir dp_dir SQL> create directory