Структура таблицы -
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Количество записей - от 50 000 до 100 000
Вот некоторые запросы к этой таблице:
1).
select "start" from "channel_program" where "channel_id" = "channels"."id" and "end" < '2019-07-02 06:10:21' order by "start" desc limit 1
2).
select "start" from "channel_program" where "channel_id" = "channels"."id" and "start" <= '2019-07-02 06:10:21' and "end" > '2019-07-02 06:10:21' limit 1
3).
select "start" from "channel_program" where "channel_id" = "channels"."id" and "start" > '2019-07-02 06:10:21' limit 1
4).
select * from "channel_program" where "start"::date = '2019-07-02' and "channel_program"."channel_id" in (14) order by "start" asc