I am using Scrolled event in collectionView for iOS. If CollectionView contains groups, e.CenterItemIndex turns to 0 each time group is changing.
Is there any way i can fix this?
private void CollectionViewtems_Scrolled(object sender, ItemsViewScrolledEventArgs e)
{
var centerItemIndex=e.CenterItemIndex;
}
On iOs: When a group of collectionView will change it starts from 0 again;
Example while Scrolling on iOS:
Index is 0
Index is 1
Index is 2
Index is 3
Index is 4
Index is 5 //After that index group will change
Index is 0
Index is 1
Index is 2 //And after that index group will change again
Index is 0
Index is 1
Index is 2
Index is 3
Index is 4
In other hand on Android index will have a continous increment
Index is 0
Index is 1
Index is 2
Index is 3
Index is 4
Index is 5 //After that index group will change
Index is 6
Index is 7
Index is 8 //And after that index group will change again
Index is 9
Index is 10
Index is 11
Index is 12
Index is 13
Related
I have a table that contains one or more records for each item. Each item can contain multiple sub-items (boards) and so the Itemid is often replicated with each record showing the division category (a number) that the Item/sub-item combo resides in:
ItemId Board# Division
142585109 0 6
142585114 0 3
142585116 0 1
142585120 0 4
142585197 0 5
142585197 2 4
142585197 3 3
142585197 5 6
142585197 8 1
142585294 0 4
142585317 0 1
I want to update the table and aggregate all of the division values (as a comma separated string) in a new field in this table, something like:
ItemId Board# AggDivisions
142585109 0 6
142585114 0 3
142585116 0 1
142585120 0 4
142585197 0 1,3,4,5,6
142585294 0 4
142585317 0 1
I used a ListAgg query to do the aggregation which works correctly but when I tried to incorporate this into an update query, I end up with multiple duplicates in the aggregated field for each record.
Here is my update attempt:
update itemtable dd
set aggregateddivisions = (SELECT Listagg(division, ',') within GROUP (ORDER BY division)
FROM itemtable ev
WHERE ev.itemid = dd.itemid
)
where exists (select 1
from itemtable ev
where ev.itemid = dd.itemid
);
How can I update the table with the aggregated list of values from the same table without ending up with duplicates?
I am a beginner for Spotfire. I have a problem about the difference calculation for the some column value. A sample table could be like this:
id timestamp state
1 7/1/2016 12:00:01 AM 1
2 7/1/2016 12:00:03 AM 0
3 7/1/2016 12:00:04 AM 1
4 7/1/2016 12:00:06 AM 0
5 7/1/2016 12:00:09 AM 1
6 7/1/2016 12:00:10 AM 0
7 7/1/2016 12:00:12 AM 1
I want to calculate the time difference for the timestamp when the state is 1,
the final table I want to have is:
id timestamp state time_diffence
3 7/1/2016 12:00:04 AM 1 3
5 7/1/2016 12:00:09 AM 1 5
7 7/1/2016 12:00:12 AM 1 3
it seems that I should identify an expression for the calculation, but I have not idea for the calculation just for one parameter :(. somebody could help me ?
still one more small question: what if the timestamp column value is just number value, how can i calculate the difference, is there any related function like DateDiff() here? for example:
id times state
1 12 1
2 7 0
3 10 1
4 11 0
5 6 1
6 9 0
7 7 1
the result could be :
id times state diffence
3 10 1 -2
5 6 1 -4
7 7 1 1
after running the code: i have the error as below:
for the row if it has the same time stamp as the last previous row, the difference will keep same as before, but actually the difference for the rows which have same time stamp would be as 0
thanks for your help :)
Assuming your data is sorted in ascending order by [timestamp] before you import it, you can partition using the Previous function with Over where the [state]=1.
Insert a calculated column with this expression:
If([state]=1,DateDiff("ss",Min([timestamp]) OVER (Previous([timestamp])),[timestamp]))
You will see it populated in your table like the below:
Then if you ONLY want to see the rows that have the difference you mentioned, on your table you can...
Right Click > Properties > Data > Limit data using expression >
And insert the expression: [time_difference] > 1
This will result in this table:
ID VALUE
0 2
1 3
2 0
When the first record with id 0 is deleted the second one should become 0 and the third one should be 1 .
Resulting in:
ID VALUE
0 3
1 0
When the record with id 1 is deleted the third one should become 1 .
ID VALUE
0 2
1 0
Which ever one is deleted the consecutive order should be maintained starting from 0.
This id is not the primary key. Should be done on delete in the trigger.
Don't modify the same table in the trigger, you will run into mutating table issues.
An alternative is to use a stored procedure and call it after you delete the record. Just select all IDs greater than your deleted ID, and subtract 1 from them.
PROCEDURE UPDATE_IDS(deletedID in Number) IS
BEGIN
UPDATE table t
SET ID = ID - 1
WHERE ID > deletedID;
END UPDATE_IDS;
My Database Table Contain Records Like this:
ID ProductId Occurences
1 1 1
2 2 5
3 3 3
4 4 3
5 5 5
6 6 8
7 7 9
Now i want to get top 4 ProductId with the highest Occurences.
This is my Query:
var data = (from temp in context.Product
orderby temp.Occurences descending
select temp).Take(4).ToList();
Now here as because ProductId 2 and 5 have same occurences and ProductId 3 and 4 also have same occurences then here I am not getting that how to resolve this means which product id should i take as because they are having same occurences.
Basically i am selecting this productid to display this products on my website.i will display those products which are return by this query.
So can anyone please give me some idea like how to resolve this ???
Expected Output:
ID ProductId Occurences
1 7 9
2 6 8
so Now for 3rd position Which ProductId i should select as because both ProductId 2 and 5 have same Occurences and for 4th position which ProductId i should select among 3 and 4 as because they both too have same occurences.
can I suggest you to use group by technique and pick the first one
context.Product.GroupBy(p => p.Occurance)
.Select(grp => grp.FirstOrDefault())
.Take(4)ToList();
Sorry, I have not tested this but it should do the job. You just need to add OrderBy along with it.
I have a table which holds more then 2 million records, I am trying to update a table using following query
UPDATE toc T
SET RANK =
65535
- (SELECT COUNT (*)
FROM toc T2
WHERE S_KEY LIKE '00010001%'
AND A_ID IS NOT NULL
AND T2.TARGET = T.TARGET
AND T2.RANK > T.RANK)
WHERE S_KEY LIKE '00010001%' AND A_ID IS NOT NULL
Usually this query tooks 5 mins to update 50000 rows in our staging db which is a exact replica of production db but in our production db it is taking 6 hours to execute...
I tried Oracle advisory to select the correct execution plan but nothing is working...
Plan
UPDATE STATEMENT ALL_ROWSCost: 329,471
6 UPDATE TT.TOC
2 TABLE ACCESS BY INDEX ROWID TABLE TT.TOC Cost: 5 Bytes: 4,173,236 Cardinality: 54,911
1 INDEX SKIP SCAN INDEX TT.DATASTAT_SORTKEY_IDX Cost: 4 Cardinality: 1
5 SORT AGGREGATE Bytes: 76 Cardinality: 1
4 TABLE ACCESS BY INDEX ROWID TABLE TT.TOC Cost: 5 Bytes: 76 Cardinality: 1
3 INDEX SKIP SCAN INDEX TT.DATASTAT_SORTKEY_IDX Cost: 4 Cardinality: 1
I can see the following wait events
1,066 db file sequential read 10,267 0 3,993 0 6 39,933,580
1,066 db file scattered read 413 0 188 0 6 1,876,464
Any help will be greatly appreciated.
here is the current list of indexes
DSTAT_SKEY_IDX D_STATUS 1
DSTAT_SKEY_IDX S_KEY 2
IDX$$_165A0002 N_LABEL 1
S_KEY_IDX S_KEY 1
XAK1_TOC N_RELATIONSHIP 1
XAK2_TOC TARGET 1
XAK2_TOC N_LABEL 2
XAK2_TOC D_STATUS 3
XAK2_TOC A_ID 4
XIE1_TOC N_RELBASE 1
XIF4_TOC SOURCE_FILE_ID 1
XIF5_TOC A_ID 1
XPK_TOC N_ID 1
Atif
You're doing a skip scan where you supposedly want to do a range scan.
A range scan is only possible when the index columns are ordered by descending selectivity - in your case it seems that it should be S_KEY - TARGET - RANK
Update: rewriting the query in different order wouldn't make any difference. What matters is the sequence of the columns in the indexes of that table.
first show us the current index columns for that table:
select index_name, column_name, column_position from all_ind_columns where table_name = 'TOC'
then you could create a new index, e.g.
create index toc_i_s_key_target_rank on toc (s_key, target, rank) compress;