Oracle

Another example of "12c more consumption than 10g index back-table" case, colleagues in 12c run the buffer get is very high, but in 10g run a low buffer. Doubt whether the 12c optimizer has a problem. This 10g environment and 12c environment, the

Cursors are divided into implicit cursors and display cursors. One, implicit cursorsThere is an implicit cursor attached to the SELECT * into and DML operations (update, delete, insert). Attributes of an implicit cursor Sql%rowcount integer

Oracle database installed on the Ali Cloud, one day received the following alerts:Name=atabasenameType=database InstanceHost=izw2519p6r9uzeeeMetric=statusTimestamp=nov, 2014 4:16:37 AM CSTSeverity=criticalmessage=failed to connect to database

In some cases, may be due to misoperation, not small first drop diskgroup, this time do not be nervous, such a failure, can be a perfect recovery through kfed (data 0 lost). If the related ASM disk is further damaged, then the subsequent recovery is

Modify Oracle Instance name System Environment: CentOS 6.5Oracle Version: 10.2 1, check the original database instance name$ echo $ORACLE _sidOrcl $ sqlplus/as SYSDBA> select instance from V$thread;INSTANCE-------------------------------------------

I want to do two sets of RAC between the data guard, because Datafile,controlfile, and even archivelog are stored on the ASM, direct copy of the data is a bit unrealistic, ASM disk is always used, so want to do from a library Rman full backup, Then

Today, in the investigation of the original code encountered a mistake, prompted the "select が@@facesymbol@@ 郡 skewer rdquo, baffled by the solution." Later foundIt's the "DISTINCT" keyword that's haunting you. My original SQL statement

Has Netizen consults the database to start the report ora-01092:oracle instance terminates. Force disconnect, request help handlingDatabase version Trace file D:\app\administrator\diag\rdbms\orcl\orcl\trace\orcl_ora_5648.trcOracle Database 11g

Sequence meaningThe Oracle database provides a sequence object, provided by the system with its own growing serial number, usually used for the growth of the primary key or ordinal number of the database data records; Nanjing OCM Training Create a

Use the following statement: O_char (pubtime, ' yyyymmdd HH:mm:ss '), for example: The code is as follows Copy Code Select Id,to_char (pubtime, ' yyyymmdd HH:mm:ss '), content from Bj_ref.gz_twinfo_ref where user_id=2603

Failure phenomenon:How do I make a cold backup of an Oracle database in case of an emergency, without opening the Oracle log archive?Solution: A cold backup of the Oracle database, sorted as follows: When do I have to use cold backup? 1. Database

VARCHAR2 (* char) and VARCHAR2 (*) A Hibernate automatic table was recently used, and when a string is used, the VARCHAR2 type field is created by default, such as setting length=10, after which the field property is Varchar2 (. Char), not VARCHAR2

There are three types of lob: Blob:binary Large Object Binary Large ObjectsClob:character Large Object single character large objectsDouble-byte Character Large Object Double Byte character large objectsLarge data types in Oracle:Long:

Date field: SQL Server Date field format in the same character field format, that is, a single quotation mark on it, Oracle Date field format is different, it is very wordy, there are only two ways to deal with: A: Add a single quotation mark to

Basic rules A. In the SPFile file, all parameters are optional, that is, you only need to list those parameters that need to be modified in the initialization parameter file, others to keep the default values. The B.spfile file can contain only

Advantages of using partitions: 1. Enhance usability: If a partition of a table fails, the data in other partitions is still available; 2, Maintenance Convenience: If the table of a section of the fault, need to repair the data, only repair the

Recently a friend accidentally caused a very big accident, I almost took a lawsuit. In doing database migration, remote misoperation deletes the original database of several databases, such as system initial installation, and the disk space usage is

Installing oracle in linux is a daunting task. Its complexity far exceeds that of installing the linux operating system. If oracle is successfully installed, some linux technologies are also mastered. This article describes how to install oracle 10

Assm level-3 bitmap is the basic skill knowledge of dba. Here we use the test method to verify the principle of level-3 bitmap.1. Create tables required for the lab environmentSQL> create tablespace a1 datafile