SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48e240e761d419cc8c01729488e0814bc15723787f5589abc6ad7b0e82c6f379' 
  AND token = 'IYvY2uTogMXgdvDc/bAlq80BUshdhAho/1qqK00faSc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

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