How to make a select that selects from the database by timestamp without taking into account the elapsed seconds?

Question

linux

Hello! such a problem, I have a database in it there is a date and time of the timestamp type, I have a script that polls the database every 10 seconds and checks if there is a record for this time, for example, an entry in the database at 16032017 21:30:00, and the script polls at 16032017 21:30:10, so I need him to understand that it is still 2130 and choose this entry for me.
There are several options but none worked for me. Date field of varchar type

('SELECT linkuser,datapost,mylinkpost FROM links WHERE datapost= UNIX_TIMESTAMP(NOW()/60*60)')
('SELECT linkuser,datapost,mylinkpost FROM links WHERE datapost= CAST(UNIX_TIMESTAMP(NOW()/60*60) AS CHAR)')
('SELECT linkuser,datapost,mylinkpost FROM links WHERE datapost= CAST((%s)/60*60 AS CHAR)',(time_now,)) # тут я передаю время сервера в timestamp
('SELECT linkuser,datapost,mylinkpost FROM links WHERE datapost BETWEEN UNIX_TIMESTAMP(NOW())-10 AND UNIX_TIMESTAMP(NOW())+10')

Answer 1

make a selection from ...: 10 to ..: 20
but in general, if this is not a Hindu legacy, then I would have thrown you out of the project for this.

Answer 2

You can get dates as strings, remove seconds and compare
The second option, look at giving as numbers subtracting extra seconds

SELECT * FROM dates WHERE (date - date % 60) = (UNIX_TIMESTAMP() - UNIX_TIMESTAMP() % 60)