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 1 
 on: April 28, 2010, 05:23:57 AM 
Started by Svek Web - Last post by Svek Web
And peak visitors now up to 10k per month (UK Based) and registration of fayres as are the directory services entries.

 2 
 on: March 08, 2010, 07:58:17 AM 
Started by Svek Web - Last post by Svek Web
But don't forget to then add yourself as a contributor!

 3 
 on: March 08, 2010, 07:57:28 AM 
Started by Svek Web - Last post by Svek Web
Lots of posts about the problems here - but all of them appear to be incomplete!

Basically it all boils down to permissions - need to run SSRS under an account that has access to SQL Server, remove anonymous authentication and make sure that the SSRS account has full permissions to the folder - then it worked for me.

 4 
 on: March 08, 2010, 07:54:07 AM 
Started by Svek Web - Last post by Svek Web
Error: The SQL Server 2005 Express Tools are installed To continue first remove the SQL Server Express 2005 tools
 
They werent installed and not in add remove programs - tried to download them again to do an uninstall no luck - then found this link and the solution worked - just load regedt32 and deleted the entry note that i didn't have sql prompt installed so i still dont know the root cause!
 
Upgrades were working fine it was only the full install that was reporting errors!

 5 
 on: March 04, 2010, 10:08:14 AM 
Started by Svek Web - Last post by Svek Web
The key tables for any sort of database index tuning are :-
sys.dm_db_index_usage_stats
sys.dm_db_missing_index_details
sys.dm_db_missing_index_groups
sys.dm_db_missing_index_group_stats

Key point though - these statistics are cumulative since the last serve restart so don't try tuning on a cold server!

Resources
dm_db_index_usage_stats - http://msdn.microsoft.com/en-us/library/ms188755.aspx
dm_db_missing_index_details - http://msdn.microsoft.com/en-us/library/ms345434.aspx
dm_db_missing_index_groups http://msdn.microsoft.com/en-us/library/ms345407.aspx
dm_db_missing_index_group_stats  http://msdn.microsoft.com/en-us/library/ms345421.aspx

Note that missing index details will be captured automatically unless SQL is started with the -x flag and that there are quite a few limitations to the missing indexes so if you've got over 500 missing index groups it's not really going to help you
 

 6 
 on: March 02, 2010, 07:59:45 AM 
Started by Svek Web - Last post by Svek Web
Dense_rank and row_number together can be used very effectively for pulling together exact matches

;with mymatches as
(
Select row_number() over(partition by houseno, add1,add2,add3, postcode order by primarykey  ) as rn
,dense_rank() over (order by houseno, add1,add2,add3, postcode) as rn2
,primarykey
from mysourcetable
)
select a.primarykey as masterpk, b.primarykey as mergepk from mymatches a join mymatches b
on a.rn2 = b.rn2 and a.rn = 1 and b.rn > 1

Gives a list of records where we have identical addresses - the dense_rank order must be identical to the partition list

 7 
 on: March 02, 2010, 07:52:59 AM 
Started by Svek Web - Last post by Svek Web
Alternative matching

Don't forget that SSIS has built in fuzzy matching algorithms - however, house numbers can cause even that problems - use a fuzzy lookup to compare the addresses although you may find that performance isn't that good on a large data set - again having at least one attribute whether it's postcode, post town or locality will allow you to match with a slightly higher performance hit.

 8 
 on: March 02, 2010, 07:48:48 AM 
Started by Svek Web - Last post by Svek Web
The best matches are normally performed on a generated match key - however - you may find it's better to isolate house numbers before matching since a lot of algorithms will see 1-11 the same as 111 and 11-1 for the house number - these are potentially all different properties though.

Again - this can be done with a replace string or a regular expression or roll your own CLR

There needs to be at least one "partially" matching key to get good results - if you have postcodes thats fine and even partial postcodes will stop you generating a cross join for all records in the database

 9 
 on: March 02, 2010, 07:43:35 AM 
Started by Svek Web - Last post by Svek Web
The quality of data varies vastly between systems and the good old soundex algorithm on SQL server is a complete waste of time for matching addresses. The main issues are
  • House Numbers are going to generate invalid keys soundex of 7 my street = 0000
  • Spaces or punctuation stop soundex from working select SOUNDEX('my house '), SOUNDEX('myhouse') returns M000 and M200

Exact matching has the same problem e.g. "my-house" and "my house" and "myhouse" are different.

One option to get round some of these problems is simply remove any none alphanumeric characters - this can be as complex as a replace statement removing any unwanted characters e.g. replace(replace(replace(field,' ',''),'-',''),'"','') etc. for any unexpected characters, or use a regular expression or a clr routine - there are a lot of published CLR routines and regular expression CLR's as examples

Other options include using a match algorithm e.g. JaroWinkler or Levenshtein on the "cleansed" addresses to see how different they are.

 10 
 on: November 14, 2009, 02:56:21 PM 
Started by Svek Web - Last post by Svek Web
We are not accepting new registrations especially if you are not UK based lol

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