spaceused of a table

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spaceused of a table

gugan_ta

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Points: 1649
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September 17, 2009 at 7:35 am

#156228

Hi,
Pls find my query
used sp_spaceused to find the size of a table1 and the result is
Table Name : table1
Rows : 12212058
reserved : 8829816 KB
data : 8828192 KB
Index size : 56 KB
unused : 1568KB
But when i copy the same table1 into Table1_copy it is showing different size
Table Name : table1_copy
Rows : 12212058
reserved : 2175448 KB
data : 2175392 KB
Index size : 16 KB
unused : 40 KB
Pls help which one is correct also if table1_copy is correct...then guide how to get correct space from table1
Note :
NO index has been created in table1 and also tried @updateusage in sp_spaceused.. but it showing
the same result
Thnaks...Gugan

Viewing 6 posts - 1 through 5 (of 5 total)

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ps. One Orange Chip Points: 29422 More actions · Answer 1

is your post incomplete? what is the query?

Pradeep Singh

Elliott Whitlow SSC Guru Points: 102402 More actions · Answer 2

I"m thinking you had a highly fragmented table that has never had an index rebuild. Does this table have a Primary Key and/or Clustered Index (usually the same one), if so it has an index. If not, then why not. When you copied the data it was copied with all the data compacted and only taking the space necessary to house it. The first table appears to have been subjected to extensive page splitting..

You need to periodically reindex your tables and update stats. The optimization jobs will help with parts of that. 8GB is big but not that big for a table..

CEWII

Bill Talada SSChampion Points: 11954 More actions · Answer 3

I'm having the same problem on a table with a varbinary(max) column. I have 21 rows at 2 MB in the varbinary(max) column totaling about 44 MB for the table but sp_spaceused shows 310 MB used. Even update statistics or reindexing doesn't change that number. If I copy the data to a new table, it will show 44 MB for the new table. In other words, I don't think reindexing is moving the off page data nor calculating its true size.

Jesse Reich Hall of Fame Points: 3020 More actions · Answer 4

Is it possible the table had a column dropped? Or an update to a previously wide column that made it smaller?

You can duplicate the problem this way:

USE tempdb

GO

IF EXISTS (SELECT * FROM sys.tables WHERE name = 'SizeCheck') DROP TABLE SizeCheck

GO

IF EXISTS (SELECT * FROM sys.tables WHERE name = 'SizeCheck2') DROP TABLE SizeCheck2

GO

CREATE TABLE SizeCheck (

ID INT NOT NULL IDENTITY(1,1) PRIMARY KEY,

Value VARCHAR(8000)

)

INSERT SizeCheck (Value)

SELECT SPACE(8000)

FROM sys.all_objects

UPDATE SizeCheck SET Value = SPACE(1)

SELECT * INTO SizeCheck2 FROM SizeCheck

EXEC sp_spaceused SizeCheck

EXEC sp_spaceused SizeCheck2

/*

name rows reserved data index size unused

SizeCheck1987 16008 KB15896 KB72 KB40 KB

SizeCheck21987 80 KB 48 KB 8 KB24 KB

*/

Bill Talada SSChampion Points: 11954 More actions · Answer 5

You got it right! I have a varbinary(max) that holds 25MB and gets updated down to 2MB but even reindexing the clustered index does not recover the space of off page data. Every row wastes 23MB of unused space that is treated as not available. I'm using ss2005.