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POLooping through database ResultSet
 

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  1. POLooping through database ResultSet
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    <p>I have a snippet of Java code here which is supposed to retrieve results from a database query and the ResultSet is supposed to iterate through the values in order to retrieve certain API data for each entry of the ResultSet. However, the problem is that I can retrieve API data for only the first entry of my ResultSet.</p> <p>This code works exactly as expected and returns all my database entries.</p> <pre><code>try { ResultSet rs; rs = stat.executeQuery("select * from schedule"); while (rs.next()) { model.addRow(new Object[]{rs.getString("SHOW"), rs.getString("SEASON")}); } } catch (Exception e) { console.append(e.getMessage() + '\n'); } </code></pre> <p>However, this code returns only the first entry.</p> <pre><code>try { ResultSet rs = stat.executeQuery("select * from schedule"); while (rs.next()) { String show = rs.getString("SHOW"); String season = rs.getString("SEASON"); String api_url = "&lt;API_URL&gt;/" + show + "/" + season; URL url = new URL(api_url); HttpURLConnection con = (HttpURLConnection) url.openConnection(); con.setRequestMethod("GET"); con.setRequestProperty("User-Agent", USER_AGENT); int responseCode = con.getResponseCode(); if (responseCode == 200) { conn_stat.setText("Connection Status : OK"); } else { conn_stat.setText("Connection Status : ERR"); } BufferedReader in = new BufferedReader( new InputStreamReader(con.getInputStream())); String inputLine; StringBuilder response = new StringBuilder(); while ((inputLine = in.readLine()) != null) { response.append(inputLine); } in.close(); String s = response.toString(); JsonArray json = JsonArray.readFrom(s); for (int i = 0; i &lt; json.size(); i++) { JsonObject show_json = json.get(i).asObject(); int episode = show_json.get("episode").asInt(); String date = show_json.get("first_aired_iso").asString(); String title = show_json.get("title").asString(); String date_formatted = date.substring(0, date.indexOf("T")); SimpleDateFormat original = new SimpleDateFormat("yyyy-MM-dd"); SimpleDateFormat target = new SimpleDateFormat("dd-MMM-yyyy"); Date unformatteddate = original.parse(date_formatted); String dateStart = target.format(unformatteddate); Date curr_date = new Date(); String dateStop = target.format(curr_date); Date d1 = null; Date d2 = null; d1 = target.parse(dateStart); d2 = target.parse(dateStop); long diff = d2.getTime() - d1.getTime(); long diffDays = diff / (24 * 60 * 60 * 1000); if (diffDays &lt; 0) { alert_model.addRow(new Object[]{show + " - " + episode, title, dateStart}); } } } } catch (Exception e) { console.append(e.getMessage() + '\n'); } </code></pre>
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    1. This table or related slice is empty.
    1. PTQuestion
    1. USKanishka Ganguly
    1. USKanishka Ganguly
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    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
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    1. This table or related slice is empty.
    1. COIf you add logging inside the loop, how many logs will be printed? Only one? Are you referencing `rs` somewhere inside the `/* DOING THINGS WITH RETRIEVED RESULT */`? Or is the code you have provided all there is? If you comment out the code below `String api_url ...` down until the closing bracket of the loop, will all records be returned (use a logger to see how many records will be returned)?
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      1. POLooping through database ResultSet
      1. USPrzemyslaw Kruglej
    2. COOnce I get the API results for a particular entry, there are no more references to the ResultSet. After that, only the JSON response from the API is manipulated. I am checking the records returned using a logger.
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      1. POLooping through database ResultSet
      1. USKanishka Ganguly
    3. CO@PrzemyslawKruglej I tried by commenting out the code, it retrieves all the data. But not otherwise.
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      1. POLooping through database ResultSet
      1. USKanishka Ganguly
 

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