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GeneralRe: Database design Pin
Jörgen Andersson18-Dec-10 12:02
professionalJörgen Andersson18-Dec-10 12:02 
GeneralRe: Database design Pin
Pete O'Hanlon19-Dec-10 9:13
mvePete O'Hanlon19-Dec-10 9:13 
GeneralRe: Database design Pin
Jörgen Andersson4-Jan-11 21:12
professionalJörgen Andersson4-Jan-11 21:12 
GeneralRe: Database design Pin
Mycroft Holmes17-Dec-10 10:57
professionalMycroft Holmes17-Dec-10 10:57 
GeneralRe: Database design Pin
Pete O'Hanlon19-Dec-10 23:20
mvePete O'Hanlon19-Dec-10 23:20 
GeneralRe: Database design Pin
Jörgen Andersson20-Dec-10 1:54
professionalJörgen Andersson20-Dec-10 1:54 
GeneralRe: Database design Pin
Mycroft Holmes17-Dec-10 10:53
professionalMycroft Holmes17-Dec-10 10:53 
GeneralRe: Database design Pin
Jörgen Andersson18-Dec-10 11:41
professionalJörgen Andersson18-Dec-10 11:41 
Mycroft Holmes wrote:
I will need to do some work to understand the relevance on the function based index


Say for example that you have a log table where one of the columns has the date datatype which carries both date and time, and you want to get all occurences from one specific day.
A query for trunc(logdate) would make a full table scan, unless you have an index on trunc(logdate).

Another example, You have a really large table where you have a status column, and the only value you ever make a search on is 'PENDING'. Then an index on "Case When status = 'PENDING' Then 1 Else Null" will be very small and fast, as only those entries where the status is PENDING will be stored in the index as null values are not indexed.

The backside is that function based indexes is costing more to maintain.

"When did ignorance become a point of view" - Dilbert

GeneralRe: Database design Pin
Mycroft Holmes18-Dec-10 12:16
professionalMycroft Holmes18-Dec-10 12:16 
GeneralRe: Database design Pin
Jörgen Andersson18-Dec-10 21:05
professionalJörgen Andersson18-Dec-10 21:05 
AnswerRe: Database design Pin
Eddy Vluggen16-Dec-10 22:15
professionalEddy Vluggen16-Dec-10 22:15 
AnswerRe: Database design Pin
Jörgen Andersson16-Dec-10 22:16
professionalJörgen Andersson16-Dec-10 22:16 
GeneralRe: Database design Pin
V.17-Dec-10 4:13
professionalV.17-Dec-10 4:13 
AnswerRe: Database design Pin
Luc Pattyn17-Dec-10 1:39
sitebuilderLuc Pattyn17-Dec-10 1:39 
GeneralRe: Database design Pin
V.17-Dec-10 4:16
professionalV.17-Dec-10 4:16 
GeneralRe: Database design Pin
Corporal Agarn17-Dec-10 9:26
professionalCorporal Agarn17-Dec-10 9:26 
GeneralRe: Database design Pin
Mycroft Holmes17-Dec-10 11:02
professionalMycroft Holmes17-Dec-10 11:02 
AnswerRe: Database design Pin
PIEBALDconsult17-Dec-10 17:51
mvePIEBALDconsult17-Dec-10 17:51 
AnswerRe: Database design Pin
David Mujica20-Dec-10 10:42
David Mujica20-Dec-10 10:42 
GeneralRe: Database design Pin
V.20-Dec-10 20:13
professionalV.20-Dec-10 20:13 
QuestionStoring images, documents etc in a database Pin
jgrogan15-Dec-10 23:48
jgrogan15-Dec-10 23:48 
AnswerRe: Storing images, documents etc in a database Pin
Mycroft Holmes16-Dec-10 0:10
professionalMycroft Holmes16-Dec-10 0:10 
AnswerRe: Storing images, documents etc in a database Pin
Hiren solanki16-Dec-10 0:41
Hiren solanki16-Dec-10 0:41 
AnswerRe: Storing images, documents etc in a database Pin
Not Active16-Dec-10 2:23
mentorNot Active16-Dec-10 2:23 
AnswerRe: Storing images, documents etc in a database Pin
RaviRanjanKr16-Dec-10 2:53
professionalRaviRanjanKr16-Dec-10 2:53 

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