APMSQL Server query is not returning any rows

Products

• CA Application Performance Management Agent (APM / Wily / Introscope)
• INTROSCOPE

Issue/Introduction

Running the following  format query returns nothing

SELECT DISTINCT agent_name
FROM numerical_metric_data
WHERE ts BETWEEN '2018-06-01' AND '2018-06-02'
AND frequency = 15000
ORDER BY agent_name DESC

if I change the query and remove the 'AND frequency = 15000' query it returns the data which seems in conflict with the documentation -

"Frequency and ts are essential. Include a number for frequency and a time stamp (that is, 'ts') attribute in every query, as you see in the following examples."

Environment

APM 10.5 and later

Cause

The reason for the no data returned is that the data crosses tier1, the frequency of the data storage changes. So after tier1 data is not stored with a frequency of 15s - default frequency for tier2 and tier3 is 60s and 900s respectively

Resolution

Change the frequency qualifier in the query from "=" to ">=" ie..

SELECT DISTINCT agent_name
FROM numerical_metric_data
WHERE ts BETWEEN '2018-06-01' AND '2018-06-02'
AND frequency >= 15000
ORDER BY agent_name DESC