Comments on: SQL SERVER – Find Largest Supported DML Operation – Question to You

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Wed, 30 Jun 2010 01:31:30 +0000

[...] How do one measure what is the largest operation of the SQL Server: SQL SERVER – Find Largest Supported DML Operation – Question to You [...]

By: Aasim Abdullah

Aasim Abdullah — Thu, 17 Jun 2010 09:54:09 +0000

Delete all (*) operation on largest table of database would be the most largest DML operation. So The log size must be at least twice the size of largest table size.

Table physical size can be obtained by…

SELECT LEFT(OBJECT_NAME(id), 30) AS [Table],dpages AS PagesUsed,
CAST(CAST(reserved * 8192 AS DECIMAL(10,1)) / 1000000.0 AS DECIMAL(10,1)) AS ‘Allocated (in M)’,
CAST(CAST(dpages * 8192 AS DECIMAL(10,1)) / 1000000.0 AS DECIMAL(10,1)) AS ‘Used (in M)’,
CAST(CAST((reserved – dpages) * 8192 AS DECIMAL(10,1)) / 1000000.0 AS DECIMAL(10,1)) AS ‘Unused (in M)’,
rowcnt AS ‘Row Count (approx.)’
FROM sysindexes
WHERE indid IN (0, 1) AND OBJECT_NAME(id) NOT LIKE ‘sys%’ AND OBJECT_NAME(id) NOT LIKE ‘dt%’
AND reserved * 8192 >= 5000000
ORDER BY reserved DESC, LEFT(OBJECT_NAME(id), 30)

By: Ramdas

Ramdas — Wed, 16 Jun 2010 17:39:58 +0000

Would this be based on the size of the largest insert into a table(s) multiplied by the number of records during a given timeframe. Really interested to know the answer(s).

By: Renju

Renju — Wed, 16 Jun 2010 04:21:48 +0000

In the performance lab of my company we had done a DML operation (data correction script) over 1 billion records over sql server 2008. Thats one of the biggest DML operation i had done. Normally our data correction script will have reverse option but here we done without that to reduce overhead.