Query tuning postgres - postgresql

Question

I'm trying to reduce response time for below postgresql query from current 5 seconds to 1...attaching explain plan too for this query..please help...
(
SELECT
1 AS RowNumber
,'Total Countries' AS RowLabel
,COUNT(DISTINCT ITS.abc CountryTrading) AS Aggregation
FROM ObjectViews.abc InstnTradeSummary AS ITS
WHERE ITS.KeyInstn = 7402194
AND ITS.TradeDataMonthYearPublish >= date_trunc('month', current_date) + interval '-5 years'
AND ITS.TradeDataMonthYearPublish <= date_trunc('month', current_date)
AND ITS.abc CountryTrading IS NOT NULL
GROUP BY ITS.KeyInstn
UNION
SELECT
2 AS RowNumber
,'Total Shipments' AS RowLabel
,SUM(ITS.ShipmentCount) AS TotalShipments
FROM ObjectViews.abc InstnTradeSummary AS ITS
WHERE ITS.KeyInstn = 7402194
AND ITS.TradeDataMonthYearPublish >= date_trunc('month', current_date) + interval '-5 years'
AND ITS.TradeDataMonthYearPublish <= date_trunc('month', current_date)
GROUP BY ITS.KeyInstn
UNION
SELECT
3 AS RowNumber
,'Total Weight in kg' AS RowLabel
,SUM(COALESCE(ITS.ShipmentWeightAR, ITS.ShipmentWeightEst)) AS TotalShipmentWeight
FROM ObjectViews.abc InstnTradeSummary AS ITS
WHERE ITS.KeyInstn = 7402194
AND ITS.TradeDataMonthYearPublish >= date_trunc('month', current_date) + interval '-5 years'
AND ITS.TradeDataMonthYearPublish <= date_trunc('month', current_date)
GROUP BY ITS.KeyInstn
UNION
SELECT
4 AS RowNumber
,'Total Volume in TEU' AS RowLabel
,SUM(COALESCE(ITS.ShipmentVolumeAR, ITS.ShipmentVolumeEst)) AS TotalShipmentVolume
FROM ObjectViews.abc InstnTradeSummary AS ITS
WHERE ITS.KeyInstn = 7402194
AND ITS.TradeDataMonthYearPublish >= date_trunc('month', current_date) + interval '-5 years'
AND ITS.TradeDataMonthYearPublish <= date_trunc('month', current_date)
GROUP BY ITS.KeyInstn
) ORDER BY RowNumber
Below is explain plan for the query...
https://explain.depesz.com/s/xgC2

Answer 1

Read the table once, do your formatting after:
SELECT
v.row_number,
v.row_label,
CASE v.row_number
WHEN 1 THEN s.total_countries
WHEN 2 THEN s.total_shipments
WHEN 3 THEN s.total_shipment_weight
ELSE s.total_shipment_volume
END AS total
FROM (
VALUES
(1, 'Total Countries'),
(2, 'Total Shipments'),
(3, 'Total Weight in kg'),
(4, 'Total Volume in TEU')
) AS v(row_number, row_label)
LEFT JOIN (
SELECT
COUNT(DISTINCT ITS.abc CountryTrading) FILTER (WHERE ITS.abc CountryTrading IS NOT NULL) AS total_countries,
SUM(ITS.ShipmentCount) AS total_shipments,
SUM(COALESCE(ITS.ShipmentWeightAR, ITS.ShipmentWeightEst)) AS total_shipment_weight,
SUM(COALESCE(ITS.ShipmentVolumeAR, ITS.ShipmentVolumeEst)) AS total_shipment_volume
FROM ObjectViews.abc InstnTradeSummary AS ITS
WHERE ITS.KeyInstn = 7402194
AND ITS.TradeDataMonthYearPublish >= date_trunc('month', current_date) + interval '-5 years'
AND ITS.TradeDataMonthYearPublish <= date_trunc('month', current_date)
GROUP BY ITS.KeyInstn
) AS s ON TRUE
ORDER BY v.row_number