SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '84abe600d0875932cdebfed3f3caa26dc394db6bc2ae9ae83b4a77950b6e53a0' 
  AND token = 'BpfuYFqHFOUgY9nJksEdYrrnpV+o1jovdx7a15hlLb0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}