Query is running very slow......

Dear Expert,

While executing the blow query, its taking too long time to fetch output.
Could you please help to fine tune the same?

SELECT
date_trunc('day', insert_time),
workflow.project.project_name,
workflow.tool_performance.project_id,
workflow.tool_performance.user_id,
workflow.tool_performance.step_id,
count(*),
round(sum(execution_time)/1000) as Sum_time_sec,
round(((round(sum(execution_time)/1000))/60)/count(*),2) as Efficency_Min,
round (((round(sum(execution_time)/1000)))/count(*),2) as Efficency_sec
FROM workflow.project,workflow.tool_performance,workflow.evidence_to_do
WHERE
workflow.evidence_to_do.project_id = workflow.tool_performance.project_id AND
workflow.evidence_to_do.project_id = workflow.project.project_id AND
workflow.tool_performance.insert_time >'2017-05-19' AND
workflow.tool_performance.insert_time <'2017-05-20' AND
workflow.evidence_to_do.status_id in (15100,15150,15200,15300,15400,15500)
Group BY
date_trunc('day', insert_time),
workflow.project.project_name,
workflow.tool_performance.project_id,
workflow.tool_performance.user_id,
workflow.tool_performance.step_id
ORDER BY
workflow.tool_performance.project_id,
workflow.project.project_name,
workflow.tool_performance.step_id

I am using PostgreSQL 9.1 with Linux Platform.

Regards,
Dinesh Chandra
|Database administrator (Oracle/PostgreSQL)| Cyient Ltd. Noida.
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