SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cdfe4aafc90cce84ee5650224b23ed84489c58648e25bce4138964f4466951af' 
  AND token = 'HBgiDnje7MlfXZ/svwzYJZv7MQkt1RfFOsS/lBu9IzM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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