I have a requirement where I need to generate Unique Application Number and in sequential format.
Sample Application Number - APP-Date-0001 the 001 will keep on increasing for entire day and counter should be reset next day. So for next day it should again start from 001 with current date.
The problem will occur when 2 users are creating application at the same time.
Keep counter and last date it was used in custom setting or similar object.
But access that custom setting with normal SOQL, not via the special custom setting methods like getInstance().
Finally - in that SOQL query use FOR UPDATE. https://developer.salesforce.com/docs/atlas.en-us.soql_sosl.meta/soql_sosl/sforce_api_calls_soql_select_for_update.htm
If 2 operations start on same time - 1 will be held until other one finishes or timeout happens
Related
In my Anylogic model I succesfully create plots of datasets that count the number of trucks arriving from terminals each hour in my simulation. Now, I want to add the actual/"observed" number of trucks arriving at a terminal, to compare my simulation to these numbers. I added these numbers in a database table (see picture below). Is there a simple way of adding this data to the plot?
I tried it by creating a variable that reads the database table for every hour and adding that to a dataset (like can be seen in the pictures below), but this did not work unfortunately (the plot was empty).
Maybe simply delete the variable and fill the dataset at the start of the model by looping through the dbase table data. Use the dbase query wizard to create a for-loop. Something like this should work:
int numEntries = (int) selectFrom(observed_arrivals).count();
DataSet myDataSet = new DataSet(numEntries);
List<Tuple> rows = selectFrom(observed_arrivals).list();
for (Tuple
row : rows) {
myDataSet.add(row.get( observed_arrivals.hour ), row.get( observed_arrivals.terminal_a ));
}
myChart.addDataSet(myDataSet);
You don't explain why it "didn't work" (what errors/problems did you get?), nor where you defined these elements.
(1) Since you want both observed (empirical) and simulated arrivals per terminal, datasets for each should be in the Terminal agent. And then the replicated plot (in Main) can have two data entries referring to data sets terminals(index).observedArrivals and terminals(index).simulatedArrivals or whatever you name them.
(2) Using getHourOfDay to add to the observed dataset is wrong because that just returns 0-23 (i.e., the hour in the current day for the current model date). Your database table looks like it has hours since model start, so you just want time(HOUR) to get the model time in elapsed hours (irrespective of what the model time unit is). Or possibly time(HOUR) - 1 if you only want to update the empirical arrivals for the hour at the end of that hour (i.e., at the same time that you updated the simulated arrivals).
(3) Using a Variable to get the database value each hour doesn't work because a variable's initial value is only evaluated once at model initialisation. You want an hourly cyclic Event in Terminal instead which adds the relevant row's value. (You need to use the Insert Database Query wizard to generate the relevant Java code for the query you need in the event's action.)
(4) Because you have a database table with specifically-named columns for each terminal (columns terminal_a and presumably terminal_b etc.) that makes it slightly more awkward. (This isn't proper relational table design where, instead of 4 columns for the 4 terminals, you'd instead have two columns for terminal_id and observed_value with a row for each time period and terminal combination.)
So your database query expression (in your Terminal agents) will need to use the SQL format (not the QueryDSL format) so that you can 'stitch in' the correct column name into the SQL.
I am new to apache flink and am trying to understand how the concept of EventTime and Windowing is handled by flink.
So here's my scenario :
I have a program that runs as a thread and creates a files with 3
fields every second of which the 3rd field is the timestamp.
There is a little tweak though every 5 seconds I enter an older timestamp (t-5 you could say) into the new file created.
Now I run the stream processing job which reads the 3 fields above
into a tuple.
Now I have defined the following code for watermarking and timestamp generation:
WatermarkStrategy
.<Tuple3<String, Integer, Long>>forBoundedOutOfOrderness(Duration.ofSeconds(4))
.withTimestampAssigner((event, timestamp) -> event.f2);
And then I use the following code for windowing the above and trying to get the aggregation :
withTimestampsAndWatermarks
.keyBy(0)
.window(TumblingEventTimeWindows.of(Time.milliseconds(4000)))
.reduce((x,y) -> new Tuple3<String, Integer, Long>(x.f0, x.f1 + y.f1,y.f2))
It is clear that I am trying to aggregate the numbers within each field.(a little more context, the field(f2) that I am trying to aggregate are all 1s)
Hence I have the following questions :
That is the window is just 4 seconds wide, and every fifth entry is
an older timestamp, so I am expecting that the next window to have
lesser counts. Is my understanding wrong here ?
If my understanding is right - I do not see any aggregation when running both programs in parallel, Is there something wrong with my code ?
Another one that is bothering me is on what fields or on what parameters do the windows start time and end time really dependent ? Is it on the timestamp extracted from Events or is it from processing time
You have to configure the allowed lateness: https://nightlies.apache.org/flink/flink-docs-release-1.2/dev/windows.html#allowed-lateness. If not configured, Flink will drop the late message. So for the next window, there will be less elements than previous window.
Window is assigned by the following calculation:
return timestamp - (timestamp - offset + windowSize) % windowSize
In your case, offset is 0(default). For event time window, the timestamp is the event time. For processing time window, the timestamp is the processing time from Flink operator. E.g. if windowSize=3, timestamp=122, then the element will be assigned to the window [120, 123).
in Salesforce, how to create a formula that calculate the highest figure for last month? for example, if I have an object that keeps records that created in Sept, now would like to calculate its max value (in this case, should be 20 on 3/8/2019) in last month's (August). If it's in July, then need to calculate for June. How to construct the right formula expression? Thanks very much!
Date Value
1/9/2019 10
1/8/2019 14
2/8/2019 15
3/8/2019 20
....
30/8/2019 15
You can't do this with normal formulas on records because they "see" only current records (and some related via lookup), not other rows in same table.
You could make another object called "accounting periods" or something like that. Link all these entries to periods (months) in master-detail relationship. You'll then be able to use rollup summary with MAX(). Still not great because you need lookup to previous month to pull it but should give you an idea.
You could make a report that achieves something like that. PREVGROUPVAL will let you do some amazing & scary stuff. https://trailhead.salesforce.com/en/content/learn/projects/rd-summary-formulas/rd-compare-groups Then... if all you need is a report - great. If you really need it saved somewhere - you could look into reporting snapshots & save results in helper object...
If you want to do it without any data model changes like that master-detail or helper object - you could also write some code. Nightly batch job (running daily? only on 1st day of month?) should be pretty simple.
Without code - in a pinch you could make a Flow that queries records from previous month. Bit expensive to run such thing for August every time you add a September record but if you discarded other options...
I am trying to match date and time, and metric category with multiple rows in a data sheet. Currently, I record metrics every day in a similar function with a set of rows showing metric data based on intervals of time. These rows are broken up by date.
I would like to be able to add to a dashboard the current metrics without someone needing to dig through the tables I am recording in. This would require the metric to stay up there until the next interval changed.
I will use =SPLIT(NOW) for the date and time but for now I would like to at least get this to work with static interval and date. I tried using Index Match using AND(), & etc and I cannot get it to work. I also tried to use an array but it errors every time.
Google Sheets Index Match Multi Criteria
If the time intervals for each day will be exactly the same and the data structure will never change with 3 identical lines per day (as per your screenshot) than I think you are overcomplicating things a little:
B2:
=index($A$7:$E$15,MATCH($A$1,$A$7:$A$15,0)+1,MATCH(B$1,$A$7:$E$7,0))
B3:
=index($A$7:$E$15,MATCH($A$1,$A$7:$A$15,0)+2,MATCH(B$1,$A$7:$E$7,0))
B4:
=index($A$7:$E$15,MATCH($A$1,$A$7:$A$15,0)+2,MATCH(B$1,$A$7:$E$7,0))
I am currently working on a requirement as follows and would appreciate some help in figuring out a way to configure the aggregation of my measure:
I have a fact table that contains the following Item ID, DateID,StoreID, ReceivedComments. The way received comments work is that on a daily basis a new record is created that adds to the value of received comments (for example if Item 5 in Store 5 on 1 Jan had 23 Received Comments and it received 5 comments the following day, the row for Jan 2 would be Item 5, Store 5, Jan 2, 28)
We created a measure using MAX and it works fine whenever Item ID is used in the query. When we start moving to a higher level the max produces wrong results. Our requirement is to setup the measure to be as follows:
If the member selected is on the Item Level then MAX, if it's on any other level (Date or Store) then the measure should aggregate the Max of all Items under this date or store.
Due to the business rules and structure of the database Store and Item are different dimensions so I can not include them in 1 Hierarchy.
We have been playing around with Custom RollUps but so far haven't been able to get it to work.
Thanks
I would solve this by using a more traditional approach to your fact table. Instead of keeping a cumulative count in the ReceivedComments column, I would keep only the number of comments received THAT DAY.
That way, instead of using MAX, you can create your measure using SUM, and it will automatically rollup when you go to higher levels.
The only disadvantage I can see to this approach is that you will need to use a range of dates, instead of only the most recent date, to get a full total of all the comments for a given item/store/date. But that's a very small change to your MDX.
Someone suggested using ISLEAF to determine the level, Instead of using ISLeaf i went with AS CASE WHEN [Item].[ItemID].CURRENTMEMBER.LEVEL IS [Item].[ItemID].[(All)] so I don't have to account for other dimensions such as Date, Store, etc as I have several other dimensions that all behave the same way.
And then I went with this formula to determine the Sum of the Max of the items in a particular store like this:
SUM({[Item].[Item ID].children},[Measures].[ReceivedComments]), Now I expect some performance issues with this measure but we are currently running some tests to see if it's gonna be reliable to work with it on actual data.