ADO.NET :: How To Check Weather The Database Is Updated Or Not
Jan 16, 2011
I have Page which has some database values in It . The current database value is say x then i want an event to be fired if the database value changes I want the Page to check the Database value in every 5 Seconds .
I am Adding Webservice Reference in my project . WSDL , Disco , XSD files are created in my project.now , my issue is how to check weather WSDL showing correct DataContracts or not. I dont want unwanted datacontracts to be downloaded .
If I store the data every second, the database will grow rapidly. I need to have less detail of measurements of a few weeks/months back. An average would be enough. I have 5 sensors: wind speed, wind direction, temperature, light and rain. How would I design my database?
protected void Button3_Click(object sender, EventArgs e) { //Create a connection to the database MySqlConnection conn = new MySqlConnection("Database=kid07025;Data Source=195.178.228.254;User Id=kid07025;Password=********"); //open the connection conn.Open(); //MySQL Query which updates the row where Anvandarnamn = Anvandarnamn (recieved from a cookie) MySqlCommand cmd = new MySqlCommand("UPDATE personer SET Information=?Information,Fnamn=?Fnamn,Enamn=?Enamn,Personnr=?Personnr,Adress=?Adress,Postnr=?Postnr,Ort=?Ort WHERE Anvandarnamn=?Anvandarnamn", conn); // Update with new text cmd.Parameters.AddWithValue("?Anvandarnamn", Request.Cookies["Anvandarnamn"].Value); cmd.Parameters.AddWithValue("?Information", TextBox1.Text); cmd.Parameters.AddWithValue("?Fnamn", TextBox2.Text); cmd.Parameters.AddWithValue("?Enamn", TextBox3.Text); cmd.Parameters.AddWithValue("?Personnr",TextBox4.Text); cmd.Parameters.AddWithValue("?Adress", TextBox5.Text); cmd.Parameters.AddWithValue("?Postnr", TextBox6.Text); cmd.Parameters.AddWithValue("?Ort", TextBox7.Text); cmd.ExecuteReader(); conn.Close(); RefreshProfile(); }
I don't know what I am doing wrong here, but the database doesn't get updated when I press the button.
I have a preferences page that has personal details of users which they are allowed to change. This data then gets put into the database but it has to be an update. My code does not show any errors it just does not update my database at all.
My previous impression of RequiredFieldValidator and similar have been that they show you an error label and set Page.IsValid false and that is it. Meaning they leave the rest of the task (preventing the use of wrong input data) to you. But today I have realised say if you use a DetailsView to insert a new record to a database, and you use validators to check the TextBoxes inside the DetailsView, they automatically prevent the database from being updated.
I would like to know how this is implemented behind the scene. I'm guessing it aborted the Page Lifecycle at Validator.PreRender event, so that database connections at later stage could not be reached? I'm probably wrong. I'm trying to use Reflector to get inside the RequiredFieldValidator to see how it is implemented, but I don't really know where to look.
i want to compare my database value with my new updated value. what should i do ? e.g : on page load i am excuting one procedure which bring 10 columns and fill it against the 10 fields using for loop on the page. then i am changing value of two columns. ok. when i press update button then there is one more procedure which updates all the new and old columns into database. Its working fine. just i want to know that, should i update only two columns(which are modified) insted of updating all 10 columns ? Is there any csharp code that brings my page load columns into array and then compare it with new ones and updates only those columns which are mismatch with array. i am not sure but there is some way to do this.
i want to use the weather web service that provided for free from webservicex so i have added the service to my ASP.net web site [URL] in the code behind i have defined an object of this service and this object require the country and city name to get the result back i gave the
city name :amman country : jordan
but i dont know how can i get back the result? is there any function i forgeted?
I have data entry form like...There are some empty rows and some of them have values. User can Update existing values and can also fill value in empty rows.I need to map these values in my DB table and some of them will be inserted as new rows into the database and existing record will be updated.I need your suggestions, How can I accomplish this scenario with best approach.
Lets take an example of online ticket booking system. Many users could be booking the tickets at any point of time. a GridView displays the list of Allotted and Free seats If a seat gets booked, this information must get updated in all the opened pages in user's browser. User need not require to refresh the page to see if a seat is booked or not Should i put GridView in update panel and keep looking into the databse constantly ??? This could turn out to be a heavy work if databse is too large any other alternative?? or should i stick with the above approach....?
I have a cascading dropdownlist. The first drop down is for Departments and is databound on PageLoad from the database. The user then selects a department and the second dropdown is populated with the appropriate sub departments via JQuery/JSON which calls an httphandler. The problem is as follows: I select a department and the subdepartments are filled.
I finish what I'm doing on that screen and everything is fine. But then if I go to a different screen and add an additional subdepartment then come back to original screen, the new sub department won't appear in the cascading dropdown. I have to close the browser and restart the session in order for any new sub departments to appear even though they are in the database. I put a breakpoint in the httphandler and noticed that it is only called once per session per each department in the first dropdown. I don't know why this is happening. I want it to call the httphander EVERY time the index of the department dropdown is changed.
I have several web sequential pages which will modify a record and its child records in the database, called a "project". Such a project is currently passed between pages using its database ID in the URL parameters.
A project has some information specific to itself, and also consists of one or more Tasks, which each have information specific to itself.
Is it faster (alternatively, more maintainable or more easily understood) to hit the database each time I need to query the same project (and its tasks), or should I query the database once (either once for each page or once for all pages and save to Session) and check the saved object rather than the database?
I want to develope charts for weather forecast sources like scadar,historical,weather and static data. Does anybody worked for these type of weather forecasting charts. what type of charts we can use for weather forecast? data will be in xml format. If user selects any datefrom and dateto, time interval according to that selection charts will be shown.
I'm currently working on a small project and therefore created a gridview, including one bit column which has been linked with a checkbox in both the itemtemplate as the edititemtemplate (autopostback = true).Databinding for these two checkboxes has been linked (two-way) to the bit column.Now I want to display the gridview to end-users. They should be able to just click on the checkbox so they value in the database column gets changed as well (as I want to run update queries behind it), but not passing via the command column 'EDIT'.=> problem I'm having now is that the bit column in the database doesn't get updated.
and the ticker data should be move right to left or from left to right into a textbox or in any other control that is more suitable for this work.i have the little idea about this that this will be imlimented with the help of ajax or java script.but the whole process is not so clear so that i start my work.