Couchbase查詢與ORDER BY DESC和LIMIT很慢

Question

select t.createdDate, t.createdDateTicks from ic_v10_mammoet t where t.type='asset' and t._sync.rev is not null ORDER BY t.createdDateTicks ASC LIMIT 10 OFFSET 0 

上述查詢花費6秒來返回結果，並且當我除去ORDER BY子句它採取只有18 MS

select t.createdDate, t.createdDateTicks from ic_v10_mammoet t where t.type='asset' and t._sync.rev is not null LIMIT 10 OFFSET 0 

我有一個索引上createdDateTicks，它是整數字段。

我試過在workaround提到的解決方法作爲最後一條評論，但這是行不通的。

有人能請指教嗎？

指數：CREATE INDEX asset_createdDateTicks ON ic_v10_mammoet (createdDateTicks) WHERE type = 'asset'

計劃with ORDER BY和計劃without ORDER BY

Answer 1

這裏是解決辦法。

CREATE INDEX idx_neg_date ON docs(-createDateTicks) WHERE type = 'asset'; 

SELECT t.createdDate, t.createdDateTicks 
FROM docs AS t 
WHERE t.type='asset' AND -t.createdDateTicks IS NOT NULL 
ORDER BY -t.createdDateTicks ASC LIMIT 10 OFFSET 0;