The Database Migration Assistant for Unicode (DMU) provides a good solution for migrating databases from legacy character sets to the Unicode character set. It is shipping with Oracle Database 12c Rel.1 and becomes the officially supported method for migration to the Unicode character set. Database Character Set Scanner (CSSCAN) and CSALTER utilities are removed from…
Leggi tutto
An interesting feature for Oracle 11g is DBMS_COMPARISON package which planned to use compare data within two schemas or between database`s schema. To use DBMS_COMPARISON you have to grant. If you connected as SYSDBA you already have had grant to execute. Other users need execute grants on DBMS_COMPARISON and that user will need to be…
Leggi tutto
Scenery: Mass distribution of rich and multimedia content over the Internet, made possible through advancements in broadband technologies, also contributes to the growth in overall data volume. The enormous growth in the volume of data that needs to be retained online makes storage one of the biggest cost elements of most IT budgets. The compression…
Leggi tutto
During Oracle OpenWorld 2016, the company has announced new version (3.4.2) of their virtualization platform Some of the key new features that have been delivered include: Oracle VM Manager support for previous Oracle VM Server releases: – Manage Oracle VM Server for x86 – 3.4.x, 3.3.x or 3.2.10/11 releases. – Manage Oracle VM Server for…
Leggi tutto
The UTL_MAIL database package is used to manage email. It allows you to send an email message directly from the database server, with cc and bcc, and also catering for RAW attachments. This package is not installed by default due to obvious security reasons, but needs to be installed manually via two scripts: utlmain.sql and…
Leggi tutto
Global Temporary Table (GTT): Data base version: Oracle Database 11g Environment: DWH This kind of table defines a temporary table for the current connection, these tables do not reside in the system catalogues and are not persistent. Temporary tables exist only during the connection that declared them and cannot be referenced outside of that connection.…
Leggi tutto
With the previous Oracle database release, long characters strings of more then 4000 bytes had to be handled using CLOB or LONG data types. Starting from Oracle 12c was introduced a new system parameter: MAX_STRING_SIZE. This parameter allows string data types to be much larger when the parameter is changed from its default value STANDARD…
Leggi tutto
In the previous releases, to be able to know the last login time of the user, we had to enable “AUDIT SESSION” and then query the AUD$ table. The SYS.USER$ table in Oracle Database 12c includes a column to store the last login time of the user. As part of the increased security features in…
Leggi tutto
In 11gr2, we now have to place the Voting Disk and Cluster Registry files on ASM disks and we do not have the option of placing them on OCFS or raw devices as in the case of previous versions. When you run the root.sh script as part of the 11gR2 RAC installation, it will create…
Leggi tutto
Have you ever been in a situation in which some database queries that used to behave well suddenly started performing poorly? More likely than not, you traced the cause back to a change in the execution plan. Further analysis may have revealed that the performance change was due to newly collected optimizer statistics on the…
Leggi tutto
Commenti recenti