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copied!<p>It'll be faster if you pull the <code>createStatement</code> out of the loop, and reuse it, rebinding the parameters each time. The <a href="https://developer.mozilla.org/en/Storage" rel="nofollow">docs for storage</a> say: "Note: If you need to execute a statement multiple times, caching the result of createStatement will give you a noticeable performance improvement because the SQL query does not need to be parsed each time."</p> <p>So instead of:</p> <pre><code>for (var i = 0; i < anchors.length; i++) { var statement = conn.createStatement("select * from links where url=?1"); statement.bindStringParameter(0, anchors[i].href); // ... do stuff with results </code></pre> <p>write:</p> <pre><code>var statement = conn.createStatement("select * from links where url=?1"); for (var i = 0; i < anchors.length; i++) { statement.bindStringParameter(0, anchors[i].href); // ... do stuff with results </code></pre> <p>Edit: Also, if you're using a recent Firefox, you can use their asynchronous API to avoid delaying the UI. Instead of calling <code>executeStep</code>, use <a href="https://developer.mozilla.org/en/mozIStorageStatement#executeAsync%28%29" rel="nofollow">executeAsync</a> instead.</p> <pre><code>statement.executeAsync({ handleResult: function(aResultSet) { // ... do stuff with results }, handleError: function(aError) { print("Error: " + aError.message); }, handleCompletion: function(aReason) { if (aReason != Components.interfaces.mozIStorageStatementCallback.REASON_FINISHED) print("Query canceled or aborted!"); } }); </code></pre>

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