Is there a “the item before this item in the BTREE index” operator?









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I need to update a record matching a secondary key where a certain timestamp field is the highest value under a certain other value. I have a composite BTREE index that covers the two relevant columns.



Is there an equivalent of Java's TreeMap.floorKey() to retrieve the corresponding value in a PostgreSQL index?



I tried Googling for a solution and found only convoluted work-arounds for what should be a very simple and specific operation.






postgresql







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  • Maybe a combination of ORDER BY, LIMIT, and OFFSET. Otherwise post more details.
    – eurotrash
    Nov 10 at 22:10














up vote
0
down vote

favorite












I need to update a record matching a secondary key where a certain timestamp field is the highest value under a certain other value. I have a composite BTREE index that covers the two relevant columns.



Is there an equivalent of Java's TreeMap.floorKey() to retrieve the corresponding value in a PostgreSQL index?



I tried Googling for a solution and found only convoluted work-arounds for what should be a very simple and specific operation.






postgresql







share|improve this question





















  • Maybe a combination of ORDER BY, LIMIT, and OFFSET. Otherwise post more details.
    – eurotrash
    Nov 10 at 22:10












up vote
0
down vote

favorite









up vote
0
down vote

favorite











I need to update a record matching a secondary key where a certain timestamp field is the highest value under a certain other value. I have a composite BTREE index that covers the two relevant columns.



Is there an equivalent of Java's TreeMap.floorKey() to retrieve the corresponding value in a PostgreSQL index?



I tried Googling for a solution and found only convoluted work-arounds for what should be a very simple and specific operation.






postgresql







share|improve this question













I need to update a record matching a secondary key where a certain timestamp field is the highest value under a certain other value. I have a composite BTREE index that covers the two relevant columns.



Is there an equivalent of Java's TreeMap.floorKey() to retrieve the corresponding value in a PostgreSQL index?



I tried Googling for a solution and found only convoluted work-arounds for what should be a very simple and specific operation.






postgresql




postgresql






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked Nov 10 at 21:50









Alex R

4,03294796




4,03294796











  • Maybe a combination of ORDER BY, LIMIT, and OFFSET. Otherwise post more details.
    – eurotrash
    Nov 10 at 22:10
















  • Maybe a combination of ORDER BY, LIMIT, and OFFSET. Otherwise post more details.
    – eurotrash
    Nov 10 at 22:10















Maybe a combination of ORDER BY, LIMIT, and OFFSET. Otherwise post more details.
– eurotrash
Nov 10 at 22:10




Maybe a combination of ORDER BY, LIMIT, and OFFSET. Otherwise post more details.
– eurotrash
Nov 10 at 22:10

















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