SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '56a013b4af19f1289d5ccdf7f82083de89d455e7aae0b181b4e1330746441956' 
  AND token = 'SIlHVH5edpUC82w2/tkZYf3HHhTozY1oPf2szxOp7Iw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}