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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PART 1 LINK Oracle VM 3-4-2 Oracle VM Manager 3.4.2 supports current and previous Oracle VM Server releases. Part 2 You can use Oracle VM Manager 3.4.2 to manage Oracle VM Server Release 3.4.x, 3.3.x, 3.2.10, or 3.2.11. If Oracle VM environment consists of Oracle VM Manager Release 3.4.2 and one or more instances of…
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DB_ULTRA_SAFE is a new parameter introduced in 11g. It provides an integrated mechanism to offer protection from various possible data corruptions. and provides critical high availability benefits for Oracle Database. Setting DB_ULTRA_SAFE initialization parameter will configure the appropriate data protection block checking level in the database. It will control DB_BLOCK_CHECKING, DB_BLOCK_CHECKSUM, and DB_LOST_WRITE_PROTECT. DB_BLOCK_CHECKING controls…
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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…
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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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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…
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The recycle bin is a data dictionary table containing information about dropped objects. Dropped tables and any associated objects such as indexes, constraints, nested tables, and the likes are not removed and still occupy space. Enabling and Disabling the Recycle Bin ALTER SESSION SET recyclebin = OFF; ALTER SYSTEM SET recyclebin = OFF; ALTER SESSION…
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SQL> select file_name from dba_data_files where tablespace_name=’TEST’; FILE_NAME —————————————————— +DATA/TEST/datafile/test_01.363.837018395 SQL> alter database datafile ‘+DATA/TEST/datafile/test_01.363.837018395’ offline; RMAN> copy datafile ‘+DATA/TEST/datafile/test_01.363.837018395’ to ‘+DATA_2’; RMAN>run { set newname for datafile ‘+DATA/TEST/datafile/test_01.363.837018395’ to ‘+DATA_2/TEST/datafile/test_01.264.837098131’ ; switch datafile all; SQL> recover datafile ‘+DATA_2/TEST/datafile/test_01.264.837098131’; SQL> alter database datafile ‘+DATA_2/TEST/datafile/test_01.264.837098131′ online; SQL> select file_name from dba_data_files where tablespace_name=’TEST’; FILE_NAME —————————– +DATA_2/TEST/datafile/test_01.264.837098131…
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ORA-01555 is caused by Oracle read consistency mechanism. When you run a select all data refer to the same “Instant”, from the first to the last selected row, for the entire duration of the processing and for how many changes are made on the selected tables from other transaction. When read consistency is not more…
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When ASM creates a datafile for a permanent tablespace (or a temporary file for a temporary tablespace), the datafile is set to auto-extensible with an unlimited maximum size and 100 MB default size. You can use the AUTOEXTEND clause to override this default extensibility and the SIZE clause to override the default size. ASM applies…
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