Helping YOU do what YOU want with YOUR data.
Welcome Guest! To enable all features please Login or Register.



Go to last post Go to first unread
#1 Posted : Tuesday, August 28, 2018 1:03:11 PM(UTC)
Rank: Advanced Member


Groups: Registered
Posts: 71

Thanks: 1 times

Hi there,

We have been trying to identify samples that have had no detects for all compounds/analytes for three or more sampling rounds. However we have found it difficult to filter out the samples that have no detects as the filter seems to target compounds/analytes rather than sample based.

Is there are way to filter out samples that have no detects for all analytes? We have tried to find a straight forward method to achieving this. What we have done so far is create tables with samples showing non-detects however this creates tables showing analytes with non-detects with blank spaces where the other analytes have detects or are not reported.

I look forward to your response.



#2 Posted : Tuesday, August 28, 2018 3:13:02 PM(UTC)
Rank: Administration


Groups: Registered, Administrators
Posts: 62

Was thanked: 1 time(s) in 1 post(s)

Hi Kate,

You should be able to get the results you’re looking for with a relatively simple multi-step filter process.

This will utilise several filters across the ‘ChemQA1_Chemistry_Samples’ and ‘ChemQA2_Chemistry_Samples_with_Raw_Results’ views.

I will use the sample database provided with ESdat for these examples.

Filter to the specific date ranges you are interested in.  There may be several ways you can do this depending on the data you have populated (Monitoring_Round, Sample_Date-Time). 

In the ‘ChemQA2_Chemistry_Samples_with_Raw_Results’ view, I am going to filter by a date range using the filter:

[Sampled_Date-Time] Between #01 Jan 2010# And #31 Jan 2010#

(You can also include other filters such as Sample_Type and Matrix_Type, to filter to the exact samples you require.)

Applying this filter will list all the results for your required date range (detects or not).

I then append ‘AND Prefix Is Null’ to the filter, which will show all the results that have detects (which is actually the inverse of what you’re looking for).  So, my filter is now:

[Sampled_Date-Time] Between #01 Jan 2010# And #31 Jan 2010# AND Prefix is Null

Switch to the filter view and check “within applied filter only”.  Select ‘SampleCode’ from the list of Fields on the left, and then press “All to Filter”.


Switch to the ‘ChemQA1_Chemistry_Samples’ view, and edit the filter to remove the ‘AND Prefix Is Null’ section.  This will list all the samples for your date range that have results (again the inverse of what you want).

One final edit to the filter will get what you’re looking for. 

Edit the filter between ‘SampleCode’ and ‘In’, type in the word ‘Not’ and click “Apply Filter”. 

Image 2

You will now have a list of all the samples in that date range that do not have any concentrations above the detection limit, which is what you are after.



You cannot post new topics in this forum.
You cannot reply to topics in this forum.
You cannot delete your posts in this forum.
You cannot edit your posts in this forum.
You cannot create polls in this forum.
You cannot vote in polls in this forum.