SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed3363baf18fb5e8085ce79c6fc74338db0727cfe617678708c31e4cc6dab2d7' 
  AND token = 'ovpLB2V8hZKIrHYjp57owVkSMIGJkg/HMk7jkrFPVAU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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