Database version : from Oracle Database 12cR1 Create sequence with session or global option When a sequence number is generated, the sequence is incremented, independent of the transaction committing or rolling back. SESSION option makes opportunity to create sequence that can used in association with global temporary table then its visibility is just for session.…
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In Oracle 12c rel.2 a great number of enhancements to the Oracle database Partitioning option have been introduced. These include: Automatic List Partitioning Filtered Partition maintenance operations Multi-Column List Partitioning Online conversion of non-partitioned to partitioned table Read-only Partitions Partitioned External Tables Automatic List Partitioning: The ability to partition a table based on distinct values…
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Until Oracle Database 12c, Oracle processes did not run as threads on UNIX and Linux systems. Every dedicated connection was represented by an operating system process. In systems where high workload was an issue, the only way to reduce CPU and memory usage was to switch from dedicated connections to shared connections using the multithreaded…
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In the previous release there was no way to control the amount of memory used by an individual PDB. It could use up lots of memory and impact the performance of other PDBs in the same instance. Oracle Database 12c Rel.2 (12.2) allows to control the amount of memory used by a PDB. PDB Memory…
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Oracle Dataguard Far Sync instance is a new feature introduced in Oracle Database 12c, which simply works like a archive/redo repeater.. Far sync instance is something different than the Oracle Database instance, as its mission is accepting redo from the primary database and then shipping that redo to other members of the Oracle Data Guard…
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The Oracle Database Firewall enables organizations to protect their databases from internal and external attacks. Oracle Database Firewall allows unauthorised SQL traffic on the network to be monitored and blocked before reaching the database. Database Firewall for Security and Compliance Oracle Database Firewall monitors and enforces normal application behavior in order to avoid the increasingly…
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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…
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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…
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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…
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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…
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