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Oracle Background Processes
Outline the names and function of Oracle background processes
vidyajnath
- Apr 23rd, 2010
The Oracle architecture has five mandatory background processes Mandatory background processes: DBWR (Database Writer) PMON (Process Monitor) CKPT (Check Point) LGWR (Log Writer) SMON (System Monitor)...
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Oracle Segments
What are the different types of segments in Oracle?
hmounir
- Apr 21st, 2010
Four types of segments are found in an Oracle database:1- Data segment every table in the database resides in a single data segment.2- Index segment each index is stored in its own index segment.3- Te...
narendra05
- Apr 16th, 2010
There are following types of segments in Oracle1. Data segments stores the data2. Index segment stores the index data3. Rollback segment : Stores undo data information for data consistency.
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Tablespace Management
What are the ways tablespaces can be managed and how do they differ?
Affrayam
- Mar 8th, 2013
The difference between LMTS & DMTS is if the extent management is local(LMTS) the information about free extents and free blocks will be maintained in DATAFILE HEADER it self AND if the extent managem...
ashdba
- Sep 5th, 2010
Tablespace can be managed by specifying Extent management local or Extent management dictionary, segment space management auto or manually by using the key words pctfree, pctused, pctincrease during tablepsace creation.
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Tablespace Fragmentation
How can you prevent tablespace fragmentation? (rebuilding, moving)?
vidyajnath
- Apr 23rd, 2010
As rows are added to tables, the table expands into unused space within the space. Conversely, when rows are deleted, a table may coalesce extents, releasing unused space back into the tablespace. As ...
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Defragmentation and Re-organization
What is the difference between defragmentation (coalescing) and re-organization (rebuilding, moving)?
Mwanamume
- Jun 21st, 2010
Defragmentation is to make data take a small space in storing (to compress data) while re-og=rganization is to rebuild or rearrange the data
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Chained / Migrated Rows
Explain about the Chained / Migrated Rows
vidyajnath
- Apr 23rd, 2010
In two circumstances, the data for a row in a table may be too large to fit into a single data block. In the first case, called chaining, the row is too large to fit into an empty data block. In this ...
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Data Integrity
How does Oracle guarantee data integrity?
kperumal75
- May 4th, 2011
Data Integrity is maintained by Triggers and various other constraints in Oracle.
kperumal75
- May 4th, 2011
Oracle Database enables you to define and enforce each type of data integrity rule defined in the previous section. Most of these rules are easily defined using either integrity constraints or datab...
