Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '802ddacaf56d4ac1465ceeb0a7e2e75a358bbe0a7baa4b03f36d1859af6998c9' 
  AND token = 'oCBrwMMhXa7cxZNAZbpWI+Zfs/GroUnFw7o2gQx5Ckw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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