extract highest row from array

Question

Team, 
 I have an array of results from query and want to use the rows which have latest timestamp. 
 So array have data like (username :abc,id,1,timestamp1) , same user have another entry but with different timestamp. Max is not doing the trick , any idea ?

ManuelHTG · Answer

Does the Dataset comes from the DB? 
 If yes, you can use a!paginginfo and with the a!sort get the data in chronological order.

Peter Lewis · Answer

You can do this using an aggregation. If you group by the username and return the MAX of the date, then it should return the most recent item. Here's an example: 
 a!queryEntity(
 entity: cons!YOUR_DSE,
 query: a!query(
 aggregation: a!queryAggregation(
 aggregationColumns: {
 a!queryAggregationColumn(
 field: "username",
 isGrouping: true
 ),
 a!queryAggregationColumn(
 field: "dateUpdated",
 alias: "dateUpdated_max",
 aggregationfunction: "MAX",
 )
 }
 ),
 pagingInfo: a!pagingInfo(
 startIndex: 1,
 batchSize: 50,
 sort: a!sortInfo(
 field: "dateUpdated_max",
 ascending: false
 )
 )
 ),
 fetchTotalCount: false
)