What are the WA_Sys_... indexes that I see on create index wizard?

[geo2500]

Hi,
When I use the Create Index Wizard, after I select a table it displays the current indexes.
The problem is that it lists an index for each column in the table although I haven't created them. (apart from the index for primary key which is auto created).
The list is like that
_WA_Sys_Column1_Number
_WA_Sys_column2_number
......

where column1,2 are the the column titles and number is a 10 digit number common to all.

If i do
exec sp_helpindex mytable

it only shows the index for the primary key.
Where are all the _WA_Sys_....???

Thanks,
George

 

[LFCfan]

Hi

these aren't indexes, they're statistics created automatically by SQL Server (I expect you have auto create/update statistics set to Yes). They are created (as far as i can tell) on columns where a query has been performed with this field in the WHERE clause, but there is no index for that column. SQL Server then creates the stats so it will be able to search on that column quicker next time such a query is run.

i hope this makes sense. also please note this is a very loose explanation!

HTH