PostgreSQL using different index for same query
I have a SQL query which is using inner join on two tables and filtering data based on several params. Going by the query plan, for different values of query params (like different date range), Postgres is using different index.
I am aware of the fact that Postgres determines if the index has to be used or not, depending on the number or rows in the result set. But why does Postgres choose to use different index for same query. The query time varies by a factor of 10, between the two cases. How can I optimise the query? As Postgres does not allows the user to define the index to be used in a query.
Edit:
explain (analyze, buffers, verbose) SELECT COUNT(*) FROM "bookings" INNER JOIN "hotels" ON "hotels"."id" = "bookings"."hotel_id" WHERE "bookings"."hotel_id" = 37016 AND (bookings.status in (0,1,2,3,4,5,6,7,9,10,11,12)) AND (bookings.source in (0,1,2,3,4,5,6,7,8,9,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70) or bookings.status in (0,1,2,3,4,5,6,7,8,9,10,11,13)) AND (
bookings.source in (4,66,65)
OR
date(timezone('+05:30',bookings.created_at))>checkin
OR
(
( date(timezone('+05:30',bookings.created_at))=checkin
and
extract (epoch from COALESCE(cancellation_time,NOW())-bookings.created_at)>600
)
OR
( date(timezone('+05:30',bookings.created_at))<checkin
and
extract (epoch from COALESCE(cancellation_time,NOW())-bookings.created_at)>600
and
(
extract (epoch from ((bookings.checkin||' '||hotels.checkin_time)::timestamp -COALESCE(cancellation_time,bookings.checkin))) < extract(epoch from '16 hours'::interval)
OR
(DATE(bookings.checkout)-DATE(bookings.checkin))*(COALESCE(bookings.oyo_rooms,0)+COALESCE(bookings.owner_rooms,0)) > 3
)
)
)
) AND (bookings.checkin >= '2018-11-21') AND (bookings.checkin <= '2019-05-19') AND "bookings"."hotel_id" = '37016' AND "bookings"."status" IN (0, 1, 2, 3, 12);
QueryPlan : https://explain.depesz.com/s/SPeb
explain (analyze, buffers, verbose) SELECT COUNT(*) FROM "bookings" INNER JOIN "hotels" ON "hotels"."id" = 37016 WHERE "bookings"."hotel_id" = 37016 AND (bookings.status in (0,1,2,3,4,5,6,7,9,10,11,12)) AND (bookings.source in (0,1,2,3,4,5,6,7,8,9,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70) or bookings.status in (0,1,2,3,4,5,6,7,8,9,10,11,13)) AND (
bookings.source in (4,66,65)
OR
date(timezone('+05:30',bookings.created_at))>checkin
OR
(
( date(timezone('+05:30',bookings.created_at))=checkin
and
extract (epoch from COALESCE(cancellation_time,now())-bookings.created_at)>600
)
OR
( date(timezone('+05:30',bookings.created_at))<checkin
and
extract (epoch from COALESCE(cancellation_time,now())-bookings.created_at)>600
and
(extract (epoch from ((bookings.checkin||' '||hotels.checkin_time)::timestamp -COALESCE(cancellation_time,bookings.checkin))) < extract(epoch from '16 hours'::interval)
OR
(DATE(bookings.checkout)-DATE(bookings.checkin))*(COALESCE(bookings.oyo_rooms,0)+COALESCE(bookings.owner_rooms,0)) > 3
)
)
)
) AND (bookings.checkin >= '2018-11-22') AND (bookings.checkin <= '2019-05-19') AND "bookings"."hotel_id" = '37016' AND "bookings"."status" IN (0,1,2,3,4,12);
QueryPlan: https://explain.depesz.com/s/DWD
postgresql indexing query-optimization
asked Nov 22 '18 at 7:06
Raman Preet SinghRaman Preet Singh
708
add a comment |
I have a SQL query which is using inner join on two tables and filtering data based on several params. Going by the query plan, for different values of query params (like different date range), Postgres is using different index.
I am aware of the fact that Postgres determines if the index has to be used or not, depending on the number or rows in the result set. But why does Postgres choose to use different index for same query. The query time varies by a factor of 10, between the two cases. How can I optimise the query? As Postgres does not allows the user to define the index to be used in a query.
Edit:
explain (analyze, buffers, verbose) SELECT COUNT(*) FROM "bookings" INNER JOIN "hotels" ON "hotels"."id" = "bookings"."hotel_id" WHERE "bookings"."hotel_id" = 37016 AND (bookings.status in (0,1,2,3,4,5,6,7,9,10,11,12)) AND (bookings.source in (0,1,2,3,4,5,6,7,8,9,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70) or bookings.status in (0,1,2,3,4,5,6,7,8,9,10,11,13)) AND (
bookings.source in (4,66,65)
OR
date(timezone('+05:30',bookings.created_at))>checkin
OR
(
( date(timezone('+05:30',bookings.created_at))=checkin
and
extract (epoch from COALESCE(cancellation_time,NOW())-bookings.created_at)>600
)
OR
( date(timezone('+05:30',bookings.created_at))<checkin
and
extract (epoch from COALESCE(cancellation_time,NOW())-bookings.created_at)>600
and
(
extract (epoch from ((bookings.checkin||' '||hotels.checkin_time)::timestamp -COALESCE(cancellation_time,bookings.checkin))) < extract(epoch from '16 hours'::interval)
OR
(DATE(bookings.checkout)-DATE(bookings.checkin))*(COALESCE(bookings.oyo_rooms,0)+COALESCE(bookings.owner_rooms,0)) > 3
)
)
)
) AND (bookings.checkin >= '2018-11-21') AND (bookings.checkin <= '2019-05-19') AND "bookings"."hotel_id" = '37016' AND "bookings"."status" IN (0, 1, 2, 3, 12);
QueryPlan : https://explain.depesz.com/s/SPeb
explain (analyze, buffers, verbose) SELECT COUNT(*) FROM "bookings" INNER JOIN "hotels" ON "hotels"."id" = 37016 WHERE "bookings"."hotel_id" = 37016 AND (bookings.status in (0,1,2,3,4,5,6,7,9,10,11,12)) AND (bookings.source in (0,1,2,3,4,5,6,7,8,9,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70) or bookings.status in (0,1,2,3,4,5,6,7,8,9,10,11,13)) AND (
bookings.source in (4,66,65)
OR
date(timezone('+05:30',bookings.created_at))>checkin
OR
(
( date(timezone('+05:30',bookings.created_at))=checkin
and
extract (epoch from COALESCE(cancellation_time,now())-bookings.created_at)>600
)
OR
( date(timezone('+05:30',bookings.created_at))<checkin
and
extract (epoch from COALESCE(cancellation_time,now())-bookings.created_at)>600
and
(extract (epoch from ((bookings.checkin||' '||hotels.checkin_time)::timestamp -COALESCE(cancellation_time,bookings.checkin))) < extract(epoch from '16 hours'::interval)
OR
(DATE(bookings.checkout)-DATE(bookings.checkin))*(COALESCE(bookings.oyo_rooms,0)+COALESCE(bookings.owner_rooms,0)) > 3
)
)
)
) AND (bookings.checkin >= '2018-11-22') AND (bookings.checkin <= '2019-05-19') AND "bookings"."hotel_id" = '37016' AND "bookings"."status" IN (0,1,2,3,4,12);
QueryPlan: https://explain.depesz.com/s/DWD
postgresql indexing query-optimization
asked Nov 22 '18 at 7:06
Raman Preet SinghRaman Preet Singh
708
@a_horse_with_no_name , edited the post.
– Raman Preet Singh
Nov 22 '18 at 7:19
Unrelated, but: the two conditions at the endAND "bookings"."hotel_id" = '37016' AND "bookings"."status" IN (0, 1, 2, 3, 12)are useless because there isWHERE "bookings"."hotel_id" = 37016at the beginning and a larger status range as well:AND (bookings.status IN (0, 1, 2, 3, 4, 5, 6, 7, 9, 10, 11, 12))
– a_horse_with_no_name
Nov 22 '18 at 7:42
It seems that with the bigger date range, the optimizer expects more rows and thus uses a different index. Does runninganalyze bookings(orvacuum analyze bookings) change anything?
– a_horse_with_no_name
Nov 22 '18 at 7:43
The differentINlists may also have an impact,
– Laurenz Albe
Nov 22 '18 at 8:40
add a comment |
I have a SQL query which is using inner join on two tables and filtering data based on several params. Going by the query plan, for different values of query params (like different date range), Postgres is using different index.
I am aware of the fact that Postgres determines if the index has to be used or not, depending on the number or rows in the result set. But why does Postgres choose to use different index for same query. The query time varies by a factor of 10, between the two cases. How can I optimise the query? As Postgres does not allows the user to define the index to be used in a query.
Edit:
explain (analyze, buffers, verbose) SELECT COUNT(*) FROM "bookings" INNER JOIN "hotels" ON "hotels"."id" = "bookings"."hotel_id" WHERE "bookings"."hotel_id" = 37016 AND (bookings.status in (0,1,2,3,4,5,6,7,9,10,11,12)) AND (bookings.source in (0,1,2,3,4,5,6,7,8,9,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70) or bookings.status in (0,1,2,3,4,5,6,7,8,9,10,11,13)) AND (
bookings.source in (4,66,65)
OR
date(timezone('+05:30',bookings.created_at))>checkin
OR
(
( date(timezone('+05:30',bookings.created_at))=checkin
and
extract (epoch from COALESCE(cancellation_time,NOW())-bookings.created_at)>600
)
OR
( date(timezone('+05:30',bookings.created_at))<checkin
and
extract (epoch from COALESCE(cancellation_time,NOW())-bookings.created_at)>600
and
(
extract (epoch from ((bookings.checkin||' '||hotels.checkin_time)::timestamp -COALESCE(cancellation_time,bookings.checkin))) < extract(epoch from '16 hours'::interval)
OR
(DATE(bookings.checkout)-DATE(bookings.checkin))*(COALESCE(bookings.oyo_rooms,0)+COALESCE(bookings.owner_rooms,0)) > 3
)
)
)
) AND (bookings.checkin >= '2018-11-21') AND (bookings.checkin <= '2019-05-19') AND "bookings"."hotel_id" = '37016' AND "bookings"."status" IN (0, 1, 2, 3, 12);
QueryPlan : https://explain.depesz.com/s/SPeb
explain (analyze, buffers, verbose) SELECT COUNT(*) FROM "bookings" INNER JOIN "hotels" ON "hotels"."id" = 37016 WHERE "bookings"."hotel_id" = 37016 AND (bookings.status in (0,1,2,3,4,5,6,7,9,10,11,12)) AND (bookings.source in (0,1,2,3,4,5,6,7,8,9,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70) or bookings.status in (0,1,2,3,4,5,6,7,8,9,10,11,13)) AND (
bookings.source in (4,66,65)
OR
date(timezone('+05:30',bookings.created_at))>checkin
OR
(
( date(timezone('+05:30',bookings.created_at))=checkin
and
extract (epoch from COALESCE(cancellation_time,now())-bookings.created_at)>600
)
OR
( date(timezone('+05:30',bookings.created_at))<checkin
and
extract (epoch from COALESCE(cancellation_time,now())-bookings.created_at)>600
and
(extract (epoch from ((bookings.checkin||' '||hotels.checkin_time)::timestamp -COALESCE(cancellation_time,bookings.checkin))) < extract(epoch from '16 hours'::interval)
OR
(DATE(bookings.checkout)-DATE(bookings.checkin))*(COALESCE(bookings.oyo_rooms,0)+COALESCE(bookings.owner_rooms,0)) > 3
)
)
)
) AND (bookings.checkin >= '2018-11-22') AND (bookings.checkin <= '2019-05-19') AND "bookings"."hotel_id" = '37016' AND "bookings"."status" IN (0,1,2,3,4,12);
QueryPlan: https://explain.depesz.com/s/DWD
postgresql indexing query-optimization
asked Nov 22 '18 at 7:06
Raman Preet SinghRaman Preet Singh
708
I have a SQL query which is using inner join on two tables and filtering data based on several params. Going by the query plan, for different values of query params (like different date range), Postgres is using different index.
I am aware of the fact that Postgres determines if the index has to be used or not, depending on the number or rows in the result set. But why does Postgres choose to use different index for same query. The query time varies by a factor of 10, between the two cases. How can I optimise the query? As Postgres does not allows the user to define the index to be used in a query.
Edit:
explain (analyze, buffers, verbose) SELECT COUNT(*) FROM "bookings" INNER JOIN "hotels" ON "hotels"."id" = "bookings"."hotel_id" WHERE "bookings"."hotel_id" = 37016 AND (bookings.status in (0,1,2,3,4,5,6,7,9,10,11,12)) AND (bookings.source in (0,1,2,3,4,5,6,7,8,9,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70) or bookings.status in (0,1,2,3,4,5,6,7,8,9,10,11,13)) AND (
bookings.source in (4,66,65)
OR
date(timezone('+05:30',bookings.created_at))>checkin
OR
(
( date(timezone('+05:30',bookings.created_at))=checkin
and
extract (epoch from COALESCE(cancellation_time,NOW())-bookings.created_at)>600
)
OR
( date(timezone('+05:30',bookings.created_at))<checkin
and
extract (epoch from COALESCE(cancellation_time,NOW())-bookings.created_at)>600
and
(
extract (epoch from ((bookings.checkin||' '||hotels.checkin_time)::timestamp -COALESCE(cancellation_time,bookings.checkin))) < extract(epoch from '16 hours'::interval)
OR
(DATE(bookings.checkout)-DATE(bookings.checkin))*(COALESCE(bookings.oyo_rooms,0)+COALESCE(bookings.owner_rooms,0)) > 3
)
)
)
) AND (bookings.checkin >= '2018-11-21') AND (bookings.checkin <= '2019-05-19') AND "bookings"."hotel_id" = '37016' AND "bookings"."status" IN (0, 1, 2, 3, 12);
QueryPlan : https://explain.depesz.com/s/SPeb
explain (analyze, buffers, verbose) SELECT COUNT(*) FROM "bookings" INNER JOIN "hotels" ON "hotels"."id" = 37016 WHERE "bookings"."hotel_id" = 37016 AND (bookings.status in (0,1,2,3,4,5,6,7,9,10,11,12)) AND (bookings.source in (0,1,2,3,4,5,6,7,8,9,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70) or bookings.status in (0,1,2,3,4,5,6,7,8,9,10,11,13)) AND (
bookings.source in (4,66,65)
OR
date(timezone('+05:30',bookings.created_at))>checkin
OR
(
( date(timezone('+05:30',bookings.created_at))=checkin
and
extract (epoch from COALESCE(cancellation_time,now())-bookings.created_at)>600
)
OR
( date(timezone('+05:30',bookings.created_at))<checkin
and
extract (epoch from COALESCE(cancellation_time,now())-bookings.created_at)>600
and
(extract (epoch from ((bookings.checkin||' '||hotels.checkin_time)::timestamp -COALESCE(cancellation_time,bookings.checkin))) < extract(epoch from '16 hours'::interval)
OR
(DATE(bookings.checkout)-DATE(bookings.checkin))*(COALESCE(bookings.oyo_rooms,0)+COALESCE(bookings.owner_rooms,0)) > 3
)
)
)
) AND (bookings.checkin >= '2018-11-22') AND (bookings.checkin <= '2019-05-19') AND "bookings"."hotel_id" = '37016' AND "bookings"."status" IN (0,1,2,3,4,12);
QueryPlan: https://explain.depesz.com/s/DWD
postgresql indexing query-optimization
postgresql indexing query-optimization
asked Nov 22 '18 at 7:06
Raman Preet SinghRaman Preet Singh
708
asked Nov 22 '18 at 7:06
Raman Preet SinghRaman Preet Singh
708
edited Nov 22 '18 at 7:18
Raman Preet Singh
asked Nov 22 '18 at 7:06
Raman Preet SinghRaman Preet Singh
708
asked Nov 22 '18 at 7:06
Raman Preet SinghRaman Preet Singh
708
asked Nov 22 '18 at 7:06
Raman Preet SinghRaman Preet Singh
708
708
@a_horse_with_no_name , edited the post.
– Raman Preet Singh
Nov 22 '18 at 7:19
Unrelated, but: the two conditions at the endAND "bookings"."hotel_id" = '37016' AND "bookings"."status" IN (0, 1, 2, 3, 12)are useless because there isWHERE "bookings"."hotel_id" = 37016at the beginning and a larger status range as well:AND (bookings.status IN (0, 1, 2, 3, 4, 5, 6, 7, 9, 10, 11, 12))
– a_horse_with_no_name
Nov 22 '18 at 7:42
It seems that with the bigger date range, the optimizer expects more rows and thus uses a different index. Does runninganalyze bookings(orvacuum analyze bookings) change anything?
– a_horse_with_no_name
Nov 22 '18 at 7:43
The differentINlists may also have an impact,
– Laurenz Albe
Nov 22 '18 at 8:40
add a comment |
@a_horse_with_no_name , edited the post.
– Raman Preet Singh
Nov 22 '18 at 7:19
Unrelated, but: the two conditions at the endAND "bookings"."hotel_id" = '37016' AND "bookings"."status" IN (0, 1, 2, 3, 12)are useless because there isWHERE "bookings"."hotel_id" = 37016at the beginning and a larger status range as well:AND (bookings.status IN (0, 1, 2, 3, 4, 5, 6, 7, 9, 10, 11, 12))
– a_horse_with_no_name
Nov 22 '18 at 7:42
It seems that with the bigger date range, the optimizer expects more rows and thus uses a different index. Does runninganalyze bookings(orvacuum analyze bookings) change anything?
– a_horse_with_no_name
Nov 22 '18 at 7:43
The differentINlists may also have an impact,
– Laurenz Albe
Nov 22 '18 at 8:40
@a_horse_with_no_name , edited the post.
– Raman Preet Singh
Nov 22 '18 at 7:19
@a_horse_with_no_name , edited the post.
– Raman Preet Singh
Nov 22 '18 at 7:19
Unrelated, but: the two conditions at the end
AND "bookings"."hotel_id" = '37016' AND "bookings"."status" IN (0, 1, 2, 3, 12) are useless because there is WHERE "bookings"."hotel_id" = 37016 at the beginning and a larger status range as well: AND (bookings.status IN (0, 1, 2, 3, 4, 5, 6, 7, 9, 10, 11, 12))– a_horse_with_no_name
Nov 22 '18 at 7:42
Unrelated, but: the two conditions at the end
AND "bookings"."hotel_id" = '37016' AND "bookings"."status" IN (0, 1, 2, 3, 12) are useless because there is WHERE "bookings"."hotel_id" = 37016 at the beginning and a larger status range as well: AND (bookings.status IN (0, 1, 2, 3, 4, 5, 6, 7, 9, 10, 11, 12))– a_horse_with_no_name
Nov 22 '18 at 7:42
It seems that with the bigger date range, the optimizer expects more rows and thus uses a different index. Does running
analyze bookings (or vacuum analyze bookings) change anything?– a_horse_with_no_name
Nov 22 '18 at 7:43
It seems that with the bigger date range, the optimizer expects more rows and thus uses a different index. Does running
analyze bookings (or vacuum analyze bookings) change anything?– a_horse_with_no_name
Nov 22 '18 at 7:43
The different
IN lists may also have an impact,– Laurenz Albe
Nov 22 '18 at 8:40
The different
IN lists may also have an impact,– Laurenz Albe
Nov 22 '18 at 8:40
add a comment |
1 Answer
1
active
oldest
votes
Finally found the solution to this problem. I am querying on the basis of more than 10 possible values of a column (status in this case). If I break this query into multiple sub-queries each querying upon only 1 status value and aggregate the result using union all, then the query plan executed uses optimized index for each subquery.
Results: The query time decreased by 10 times by this change.
Possible explanation for this behaviour, the query planner fetches less number of rows for each subquery and uses the optimized index in this case. I am not sure about if this is the correct explanation.
answered Dec 18 '18 at 14:02
Raman Preet SinghRaman Preet Singh
708
add a comment |
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Finally found the solution to this problem. I am querying on the basis of more than 10 possible values of a column (status in this case). If I break this query into multiple sub-queries each querying upon only 1 status value and aggregate the result using union all, then the query plan executed uses optimized index for each subquery.
Results: The query time decreased by 10 times by this change.
Possible explanation for this behaviour, the query planner fetches less number of rows for each subquery and uses the optimized index in this case. I am not sure about if this is the correct explanation.
answered Dec 18 '18 at 14:02
Raman Preet SinghRaman Preet Singh
708
add a comment |
Finally found the solution to this problem. I am querying on the basis of more than 10 possible values of a column (status in this case). If I break this query into multiple sub-queries each querying upon only 1 status value and aggregate the result using union all, then the query plan executed uses optimized index for each subquery.
Results: The query time decreased by 10 times by this change.
Possible explanation for this behaviour, the query planner fetches less number of rows for each subquery and uses the optimized index in this case. I am not sure about if this is the correct explanation.
answered Dec 18 '18 at 14:02
Raman Preet SinghRaman Preet Singh
708
add a comment |
Finally found the solution to this problem. I am querying on the basis of more than 10 possible values of a column (status in this case). If I break this query into multiple sub-queries each querying upon only 1 status value and aggregate the result using union all, then the query plan executed uses optimized index for each subquery.
Results: The query time decreased by 10 times by this change.
Possible explanation for this behaviour, the query planner fetches less number of rows for each subquery and uses the optimized index in this case. I am not sure about if this is the correct explanation.
answered Dec 18 '18 at 14:02
Raman Preet SinghRaman Preet Singh
708
Finally found the solution to this problem. I am querying on the basis of more than 10 possible values of a column (status in this case). If I break this query into multiple sub-queries each querying upon only 1 status value and aggregate the result using union all, then the query plan executed uses optimized index for each subquery.
Results: The query time decreased by 10 times by this change.
Possible explanation for this behaviour, the query planner fetches less number of rows for each subquery and uses the optimized index in this case. I am not sure about if this is the correct explanation.
answered Dec 18 '18 at 14:02
Raman Preet SinghRaman Preet Singh
708
edited Dec 19 '18 at 7:23
answered Dec 18 '18 at 14:02
Raman Preet SinghRaman Preet Singh
708
answered Dec 18 '18 at 14:02
Raman Preet SinghRaman Preet Singh
708
answered Dec 18 '18 at 14:02
Raman Preet SinghRaman Preet Singh
708
708
add a comment |
add a comment |
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@a_horse_with_no_name , edited the post.
– Raman Preet Singh
Nov 22 '18 at 7:19
Unrelated, but: the two conditions at the end
AND "bookings"."hotel_id" = '37016' AND "bookings"."status" IN (0, 1, 2, 3, 12)are useless because there isWHERE "bookings"."hotel_id" = 37016at the beginning and a larger status range as well:AND (bookings.status IN (0, 1, 2, 3, 4, 5, 6, 7, 9, 10, 11, 12))– a_horse_with_no_name
Nov 22 '18 at 7:42
It seems that with the bigger date range, the optimizer expects more rows and thus uses a different index. Does running
analyze bookings(orvacuum analyze bookings) change anything?– a_horse_with_no_name
Nov 22 '18 at 7:43
The different
INlists may also have an impact,– Laurenz Albe
Nov 22 '18 at 8:40