Have to find a count of rows from my postgresql query - postgresql

Hi I tried to get a count of rows from my below query:
select count(substring(wsresult_question FROM '[0-9]+') as pumporder) AS totals,
job_id,
job_siteid,
job_completed
from webserviceresults w, jobs s
where job_siteid = '1401'
and job_id = wsresult_jobid
and job_completed is not null
and wsresult_question LIKE 'job.job_site_data.site_meters.pump.%'
and wsresult_category = 'Job'
group by pumporder,job_id,job_siteid,job_completed order by job_completed desc
I tried this and i got the error like
There was an SQL error:
ERROR: syntax error at or near "as" LINE 1: ... count(substring(wsresult_question FROM '[0-9]+') as pumpord... ^
In this line substring(wsresult_question FROM '[0-9]+') as pumporder I just tired to get only a number from some concatenate strings. The concatenate string is being like
1.job.job_site_data.site_meters.pump.0.meter_calibration_record.meter_adjustedtofast
2.job.job_site_data.site_meters.pump.0.meter_calibration_record.meter_adjustedtoslow
3.job.job_site_data.site_meters.pump.1.meter_calibration_record.meter_adjustedtofast
So substring(wsresult_question FROM '[0-9]+') as pumporder is return the numbers like 0,1 in array. I need to total the count of rows now. So Kindly help me on this.
Please let me know if you have any queries.
Thanks in advance!

your error means you should not create an alias for the function - only for the column, so if you remove as pumporder from count(substring(wsresult_question FROM '[0-9]+') as pumporder) , error will go away
Your approach though is very doubtful. If you want to count number of rows with substring(wsresult_question FROM '[0-9]+'), you better instead:
select count(1) AS totals,
job_id,
job_siteid,
job_completed
from webserviceresults w, jobs s
where job_siteid = '1401'
and job_id = wsresult_jobid
and job_completed is not null
and wsresult_question ~ '^(job.job_site_data.site_meters.pump.)[0-9]'
and wsresult_category = 'Job'
group by pumporder,job_id,job_siteid,job_completed order by job_completed desc
and lastly the string job.job_site_data.site_meters.pump.0 looks like json path, so it would be more appropriate using json array length function, not count on rows

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