SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d3793f672622ee0346aedf4ec25ec7ae4aca2e2826025c0fb4d14727dd425a7' 
  AND token = 'Y6VhXGzWf8z2CiI8WzXCjoYYhbSt8Y1hqQfVuZwYaR0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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