What does coalescing a tablespace do?

Answers were Sorted based on User's Feedback



What does coalescing a tablespace do?..

Answer / guest

A free extent in a dictionary-managed tablespace is made up
of a collection of contiguous free blocks.

When allocating new extents to a tablespace segment, the
database uses the free extent closest in size to the
required extent. In some cases, when segments are dropped,
their extents are deallocated and marked as free, but
adjacent free extents are not immediately recombined into
larger free extents. The result is fragmentation that makes
allocation of larger extents more difficult.

Oracle Database addresses fragmentation in several ways:

When attempting to allocate a new extent for a segment, the
database first tries to find a free extent large enough for
the new extent. Whenever the database cannot find a free
extent that is large enough for the new extent, it
coalesces adjacent free extents in the tablespace and looks
again.

The SMON background process periodically coalesces
neighboring free extents when the PCTINCREASE value for a
tablespace is not zero.

If you set PCTINCREASE=0, no coalescing of free extents
occurs. If you are concerned about the overhead of ongoing
coalesce operations of SMON, an alternative is to set
PCTINCREASE=0, and periodically coalesce free space
manually.

Manually Coalesce any adjacent free extens user this
command:
ALTER TABLESPACE <<TABLESPACENAME>> COALESCE

Is This Answer Correct ?    18 Yes 1 No

What does coalescing a tablespace do?..

Answer / prashe

Coalescing is only valid for dictionary-managed tablespaces
and de-fragments space by combining neighboring free extents
into large single extents.

Is This Answer Correct ?    5 Yes 5 No

Post New Answer

More Oracle AllOther Interview Questions

Is there any link between pr form(purchse requisition)and po form(purchase order)

0 Answers   L&T,


How client makes connection with server in client/server architecture?

1 Answers   CA,


please send me oracle pl/sql exp resume. and also faqs...

0 Answers  


How I can load an image into image item on Forms. I want to know about built-ins and procedure. and also code for it.

0 Answers  


Name a tablespace automatically created when you create a database.

3 Answers   HCL,






What is index? How many types of indexes?

2 Answers   HCL,


Differentiate between writeoff and receipt writeoff. : oracle accounts receivable

0 Answers  


What is chargeback invoice? How do we create it? : oracle accounts receivable

0 Answers  


TILL WHAT LEVEL OF SECURITY BO SUPPORTS?

1 Answers  


IS IT POSSIBLE TO CREATE REPORTS FROM DIFFERENT UNIVERSES IN ONE DOCUMENT?

0 Answers  


What is mrc and what is its use? : oracle accounts receivable

0 Answers  


Tell me about entire study of finacle software as soon as possible? give me the idea about questions which coulb be asked in interview of pnb it officers?

0 Answers   Punjab National Bank,


Categories
  • Oracle General Interview Questions Oracle General (1789)
  • Oracle DBA (Database Administration) Interview Questions Oracle DBA (Database Administration) (261)
  • Oracle Call Interface (OCI) Interview Questions Oracle Call Interface (OCI) (10)
  • Oracle Architecture Interview Questions Oracle Architecture (90)
  • Oracle Security Interview Questions Oracle Security (38)
  • Oracle Forms Reports Interview Questions Oracle Forms Reports (510)
  • Oracle Data Integrator (ODI) Interview Questions Oracle Data Integrator (ODI) (120)
  • Oracle ETL Interview Questions Oracle ETL (15)
  • Oracle RAC Interview Questions Oracle RAC (93)
  • Oracle D2K Interview Questions Oracle D2K (72)
  • Oracle AllOther Interview Questions Oracle AllOther (241)