Oracle

Recently, a machine equipped with Rhel5.3 40G memory has an Oracle database, the database of the SGA set to 20G, when running a business, a peak of business, find swap frequent swap, CPU 100%,load is very high, basically reflected in insufficient

--oracle How to bulk export the database table structure (build table statement)--1. Use the System user creation path Utl_dir to hold the file-D:\HSX\DBA must be a pre-existing directory create or replace directory Utl_dir as ' D:/HSX/DBA '; --Log

Source: http://blog.csdn.net/zhrzhl/article/details/24020319 1. ORACLE SID View Settings View SID, User name $ env|grep SID, select * from V$instance, select Instance_name,host_name from V$instance; View all users and user status of the database:Sql>

Sometimes we need to migrate the data of the database, but some data will not let the migration in the case of partial table export Import. ----Data export--Create a directory to put DMP filesMkdir-p/backup/oracle/dmp --Assign value to Oracle

Oracle does not distinguish between tables or indexes in the table space, all the tables and indexes can be placed in the same table space when the amount of data is more than an hour, but as the volume of data increases, it is best to store the

In ORACLE database, you need to SQLStatement to optimize the words need to know its implementation plan, and accordingly to adjust. There are several ways to get Oracle's execution plan, and here's a summary1, the use of explain     Oracle RDBMS

Sql> CREATE TABLE T_long (ID number, long_col LONG); 　　Table has been created. 　　Sql> INSERT into T_long VALUES (1, Lpad (1, 32767, ' HELLO world! ')); 　　1 lines have been created. 　　Sql> COMMIT; 　　Submit completed. 　　Sql> SELECT * from T_long WHERE

Oracle jobs have functions that are timed to perform tasks at a specified point in time or at a point in time each day. And after Oracle restarts, the job continues to run without restarting. first, in the query system Job , you can query the view --

Creating partitions is a means of database optimization, and range partitioning is one of the table partitions. The key word for creating a range partition is "range", where the data can be distributed according to the range specified by the

Similar to other database systems, Oracle string concatenation uses the "| |" string concatenation, which is used in the same way as the plus sign "+" in MSSQLServer. For example, execute the following SQL statement: SELECT ' work # for ' | |

-----Create a table space Create tablespace mytablespace_1 datafile ' c:/oracle/product/10.1.0/oradata/mydata/mytablespace1.dbf ' size 100m Extent management Local uniform size 256K Create tablespace mytablespace_2 datafile '

When the partition1. Tables larger than 2GB2. With 10 million records above, the more data that is contained in the table, the slower the SQL operation will be executed.3. A table that will contain a large amount of data.4. A table that can be used

Last quarter all months:SELECTTo_char (Add_months (Add_months (TRUNC (Sysdate,'YYYY'), A* 3),-ROWNUM),'yyyymm') Last_q from(SELECTTo_char (Sysdate,'Q')-1A fromDUAL) CONNECT byROWNUM 3 ORDER by 1;All months of the quarter: SELECTTo_char

First, the host descriptiondbprimary:192.168.1.57 Host name DB1DBSTANDBY:192.168.1.58 Host name DB2Sid:orclSecond, the configuration of TNS, the configuration of the file content:Dbprimary Listener.ora (/db/app/oracle/product/11.2.0/network/admi

Select(Case when To_char (Sysdate,'MM')=' on'Then'A'When to_char (Sysdate,'MM')=' Geneva'Then'B'When to_char (Sysdate,'MM')='Geneva'Then'C'When to_char (Sysdate,'MM')='Geneva'Then'D'When to_char (Sysdate,'MM')=' to'Then'E'When to_char (Sysdate,'MM')=

1. ORACLEBACKUP_EXPDP version|oracle.batThe file also needs to be changed manually as follows: The calling format needs to be changed to the call%~dp0\oraclebackup databaseUser namePasswordfolder name；2.Oracle Statement Create export path. txtThe

1. Determine the range of SCN and get gap log sequence via alert logGap-thread 1 Sequence 109631-1171702, according to the sequence to obtain the starting point SCNTip The minimum gap sequence is 109631, push forward a sequence, and then obtain the

Ways to start Scott users in Oracle 11GR2The method for starting Scott users in Oracle, in Oracle11gr2, (g for ' network ') database in which Scott was locked in the user's installation ,When you install Oracle, you can choose to unlock the user

Oracle has a high-speed buffering concept, which is to store executed SQL statements, which Oracle does a lot of work when executing SQL statements, such as parsing SQL statements, estimating index utilization, binding variables, reading blocks, and

Oracle Database Composition:Consists of two parts: Oracle database and database instance;A database is a collection of data files, which is the Oracle background process/thread and the shared memory area allocated by the server;Querying the current