Generic extraction

[Former Member]

In generic extraction, under generic delta setting,

delta field is changed On

if the lower safety limit is 1, rsa7 delta pointer for changed_on is 06/18/07(extarction done on 06/18 at 1AM),then what is the selection range for changed on parameter for next extract on 06/18/07 at 1PM.

When I tested the system is getting 06/18/07 and from and to range for changed on. I thought the system would get 06/17/07 to 06/18/07 as the lower safety limit is 1day.

Please explain this behavior.

[Former Member · Accepted solution]

I don't undertand.

If the lower safety interval limit is 1 and Iam extacting today 6/27 at 5:30PM, with the last delta done is on 6/27 at 1AM, then, would that not mean to extarct today plus today-1 data(6/27 and 6/26). Thatz why you call it saftey interval, meaning that you wnat to pick any transactions that you might have missed in the previous delta.

Similary, if I give a lower saftey of 1 and upper as 30min, what would this mean?

I wold say, the system should extarct all transactions made on 6/26 plus 6/27(except all the transactions created bet 5:15 to 5:30)

Anybody to make me understand. Thanks.

[Former Member · Accepted solution]

I lost my cycle - it was worth 500 bucks. Now I had to buy another one for 800 bucks.

I say I effectively lost 1300 bucks.

That is what you are saying.

[Former Member · Accepted solution]

Assume Last Delta Load 06/27 <u>1AM</u> (Last Delta 06/26 (06/25 -1 +1) to 06/27)

Safety Lower Interval: 1

It will extract only 06/27 (06/27 - 1 + 1). You won't get 06/26 data ( Delta for 06/27 already loded).

Safety Lower Interval: 1

Safety higher Interval: 1

Lower limit will be determined same as mentioned above... it will extract 06/27 only.

Higher limit will be next day i.e. 06/28/2007.

Date Range 06/27 to 06/28.

Reason: By default(with 0 Limits), you can extract delta only once. That Delta already happend for 06/27 at 1AM (If you run delta again without setting Lower Limit, you will get 0 records.). If you set Lower Limit 1, you are gettting flexibility to load records created on 06/27. You running delta on the Same Date that is why you couldn't able to date Range.

<u>Formula System using in the Background: Last Delta - Safety Lower Limit + 1.</u>

Nagesh Ganisetti.

• Assign points if it helps.

[Former Member · Accepted solution]

Sorry Ajay! what?

[Former Member · Accepted solution]

Never mind.

Are you still unclear on safety interval lower limit?

[Former Member · Accepted solution]

Nagesh,

Thanks for your explanation. It was very helpful for lower safety limit.

Please give the formula for higher safety limit and an example. Thanks.

Simmi

[Former Member · Accepted solution]

Hello Ajay,

if you can answer, please do. I don't see any point with abrupt responses . Thanks for your participation.

[Former Member · Accepted solution]

<i>"If the lower safety interval limit is 1 and Iam extacting today 6/27 at 5:30PM, with the last delta done is on 6/27 at 1AM, then, would that not mean to extarct today plus today-1 data(6/27 and 6/26)."</i>

--> No that doesn't. If you have delta on a CALDAY type field, the time of extraction is nowhere in picture. In this case if the last delta was done on 06/27 (assuming there is no upper limit specified) it brought delta upto 06/27. The next delta will pick records from

---06/28 if there was no lower limit for safety interval

--06/27 if there was a lower limit of 1.

<i>" Thatz why you call it saftey interval, meaning that you wnat to pick any transactions that you might have missed in the previous delta."</i>

(Only)This part of your message is exactly right.

<i>Similary, if I give a lower saftey of 1 and upper as 30min, what would this mean?

I wold say, the system should extarct all transactions made on 6/26 plus 6/27(except all the transactions created bet 5:15 to 5:30)</i>

You are again mixing the 500 with 800. Please make your mind whether the delta field is of date type or timestamp type. If it is of date type, the limits would be in days (ie 30 days not 30 minutes in lower limit in this case). And the time of extraction, for the second (and every time henseforth) time has no relevance if your delta field is of CALDAY type. It will only consider the date of extraction, not time.

To cut it short, lower limit really is not a useful thing in most circumstances, and creates more confusion than it is worth. But it logically works just as it claims to do.

The point (of the abrupt post) was that the answer can at best be as intelligent as the question.

[Former Member · Accepted solution]

Higher Limit = last Delta + Limit + 1.

without Limit... Last Delta (06/26) + 0 + 1 = 06/27

as Ajay mentioned, Time won't be considered if your delta working on Calender Day.

All our Generic Extractors build with Lower Limit '2'. it really helped us (only for Extractor build with views).

Hope this helps.

Nagesh Ganisetti.

• Assign points if it helps.

[Former Member · Accepted solution]

Okay got it. I will stand on one specific delta type.

what would be the similar formulas for time Stamp and Numeric pointer type.

Also, does the usage of higher limit make sense only in case of Time TSamp type generic delta? Because, if I am using 0calday, upper limit 1 and no lower limit with last delta on 06/27 and next dalta on 06/28, the selection for 0claday would be from 06/28 to 06/29( 06/2711) and this does not make sense. Please explain.

Simmi

[Former Member · Accepted solution]

I got a chance to Debugg while i'm using Calday for Delta. I didn't check for Time Stamp.

I guess Number Pointer will work in the Same way.

Nagesh Ganisetti.

[Former Member · Accepted solution]

Hello Nagesh,

I was talking about the Highr Safety Limit formula you mentioned.

if I am using 0calday, upper limit 1 and no lower limit with last delta on 06/27 and next dalta on 06/28, for 06/28 extraction run,the selection for 0claday would be from 06/28 to 06/29( 06/2711) and this does not make sense. Please explain.

Also, the default 1 used in your formuals(last delta-limt)1;last deltalimt+1----what would that be for time-stamp and Numaeric pointers?What would be the formuals as well?

Thanks

Simmi

[Former Member · Accepted solution]

Upper limit adjusts 'backwards' just like the lower limit.

Let us say it is set to 1 for calday. You extract on 06/25. It will bring data upto 06/24. Next you run it on 06/27 - it will bring data from 06/25 to 06/26.

The limits work the same for numeric pointer and timestamp. In case of numeric pointers they adjust the field value by the specified no, in second case by that many 'seconds'.

<a href="https://wiki.sdn.sap.com/wiki/display/profile/2007/06/29/Generic+Delta">This</a> might be of use.

[Former Member]

Thanks Guys! you are amazing.

[former_member183777]

If you used the interval of 2 days, you would get 6/17 to 6/18. The safety interval works with the last load date(in this case). If safety interval was blank and your next delta load was on 06/19, then I think you would get a range of 6/19 to 6/19. If next delta load was on 06/20 instead you would get a range of 06/19 - 06/20. In other word the lower limt of the delta load is ((last load date +1) - lower safety interval).

The Upper interval works to change to to date of the range.

If ever the from date becomes more than to date it is reduced to the to date.

I haven't tried all these cases but it is easy enough to verify.