SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a71d62ee705633d68c9d67d30cd5192358f0091459f48492c0c0988f37181d9c' 
  AND token = 'd2jc/1MOp5YJBXujXtu9w++SSuy6Y85AUdJgoxWB4GI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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