postgresql - How to fetch next unique row from a table of postgres -


suppose table contains 2 columns "id" (type character varying(22)) , "time" (type timestamp without time zone).

now have data in table follows,

id        time p001     2015-02-04 10:00:00 p002     2015-02-04 10:00:00 p003     2015-02-04 10:00:00 p004     2015-02-04 10:10:00 p005     2015-02-04 11:00:00

query first row be:

select * <tablename> order time, id limit 1;

after query next row having id value "p002"

generally offset, if there's index on time, id can more efficient database (only noticable if have millions of rows though).

standard solution:

select * <tablename> order time, id limit 1 offset 1;

indexed (usually faster) solution:

select * <tablename> time >= '2015-02-04 10:00:00' , id > 'p001' order time, id limit 1;

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