The Apptio Datalink Connector for connecting to the VMware VCenter includes some recommended SQL to pull the attributes used by our configuration.

I tested the SQL suggestion for the Hypervisor Hosts against my customer's VCenter.  Once I connected I got an empty set back (no rows!).  

I went back and tested each of the subqueries that are joined using inner joins.  I found that this particular INNER JOIN had an empty set return on the subquery.

INNER JOIN
(
select substring(ENTITY, 6, 100) as HOSTID,
(max(stat_value)/(SAMPLE_INTERVAL*1000))*100 as PEAK_TOTAL_CPU_READY_PERCENT,
(avg(stat_value)/(SAMPLE_INTERVAL*1000))*100 as AVG_TOTAL_CPU_READY_PERCENT
from dbo.VPXV_HIST_STAT_MONTHLY
where ENTITY like 'host-%' and stat_group='cpu' and STAT_NAME='ready'
GROUP BY ENTITY, SAMPLE_INTERVAL
) AS cpuUsage ON vh.HOSTID = cpuUsage.HOSTID

When I commented out the where clause, and added the ENTITY, stat_group, and stat_name into the query, I found that, at least for this client, there was no stat_name called "ready".  there was usage, and usagemhz.

Is it possible that not every vCenter is configured to capture the stat_name "ready"?  If so, maybe making this join a LEFT JOIN would make it so if these particular stat's fail it doesn't torpedo the entire query.

What do the experts say?

Hi Dan, can you confirm what version of vCenter your customer is running?

From their vcenter: VMware ESXi 6.0.0 build-3620759

I don't have a firm answer as to why you don't have "ready" in your system but here are a couple of links that may help provide some context to support any changes you need to make to the query for this particular case:

Querying the VMware vCenter Database (VCDB) for Performance and Configuration Information - Jonathan Kehayias 

Guest CPU/Memory Usage in vCenter database | VMware Communities 

Thanks Ken.  These are some good articles.  I'm going to pursue using an average and max of the usagemhz to get at CPU utilization in lieu of ready state and communicate that back to the client.