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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '68110d001628d6e94160667f07ebeb991cbadf3d4d8d60852d2ef5aefdffc24b' 
  AND token = 'VUOU3CbZFh1x2BfFO1sbhjGhpTuyWO8O6MZHTjLdI18=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

Explain
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE								Impossible WHERE noticed after reading const tables