How should I combine array values?

pete letkeman

I have the following:

I want to replace userId:[3,14,2] with userIds: '3,14,2'.

Essentially I want to do a JOIN on the array.

I could have maybe 100 different JSON objects with arrays containing maybe 100 elements.

I can loop through all of the JSON objects in the result and then loop through all userIds appending them to a string variable. That is easy enough, but is that the best way to do this?

Could this be done with Lambdas? If so please provide some examples.

I would like to do the same with securityGroupId and securableEntityId.

pete letkeman

@Michael Udinski, sorry not exactly what I'm asking, let me try again.

I have 100 records, each with an array that can have up to 100 values.

I am NOT updating the database.

I want to take each array and do an array.join (https://www.w3schools.com/jsref/jsref_join.asp) so that instead of an array of 100 values I have a single string with all of the values commas separated, and I want to keep the other values or the record as is.

I CAN do this easily enough in Xano with a variable and a couple of loops.

---------------

string temp = ''

select fld1, fld2, fld3 from table1 as results

for each record in results

  for each value in record[fld1]

      temp = temp + ',' + value

  next

  record.flat = temp

  temp = ''

next

----------------------

Is this the best and/or only way to do this with Xano?

However, I want to do:

select GROUP_CONCAT(fld1) as flat, fld2, fld3 from table1 as results

(https://www.w3resource.com/mysql/aggregate-functions-and-grouping/aggregate-functions-and-grouping-group_concat.php)

But, if I can't use group_concat or something like that then can I do something with a Lambda expression to get the result that I want?

Ray Deck

Most db-level functions aren't available in-query, but you can do them in the function stack. Xano supports a join filter (documented here https://docs.xano.com/working-with-data/data-type-filters/array-filter) that concatenates your array into a string without the inner loop- should be much faster.

We discuss these kinds of data manipulation questions on our State Change Pro office hours on a daily basis. Our next is tomorrow!

Michael Udinski

@pete letkeman if you want to replace something with another value then you can use Update Variable. If you are wishing to combine two arrays then I would use the Merge filter or function Array: Merge.