check if string is null in sql RSS

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  troika

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  check if string is null in sql

  Jan 26, 2013 12:54 AM|LINK

  i have a listview with items and i can check some category, some item details, or returns a null image link a load a default image but i miss something because command is wrong

  SELECT IIF(ISNULL(Atleta.url_imagem), 'no_photo.jpg', Atleta.url_imagem) as URLImagem, Atleta.id, Atleta.nome,  Categoria.nome AS Expr1, Atleta.id_categoria FROM Atleta INNER JOIN Categoria ON Atleta.id_categoria = Categoria.id WHERE ((? = 0) or (Atleta.id = ?)) and ((? = 0) or (Atleta.id_categoria = ?)) order by Atleta.nome

  • Edited by troika on Jan 26, 2013 09:28 AM
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  alankarp

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  Re: check if string is null in sql

  Jan 26, 2013 04:36 AM|LINK

  try this

  SELECT ISNULL(Atleta.url_imagem,'no_photo.jpg') as urlimagem, Atleta.id, Atleta.id_categoria, Categoria.nome AS Expr1, Atleta.id_categoria
  FROM Atleta INNER JOIN Categoria ON Atleta.id_categoria = Categoria.id WHERE
  ((? = 0) or (Atleta.id = ?)) and ((? = 0) or (Atleta.id_categoria = ?))
  order by Atleta.nome

  No need to use IIF
  
  

  Alankar Patil
  
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  oned_gk

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  Re: check if string is null in sql

  Jan 26, 2013 05:45 AM|LINK

  You can simply replace the null image in ASP.NET page

  <asp:Image ID="Image1" runat="server"
        ImageUrl='<%# isdbnull(Eval("url_imagem")) ? "no_photo.jpg" : Eval("url_imagem") %>' />

  
  
  

  Programming to simplify, dont look for hard way
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  troika

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  Re: check if string is null in sql

  Jan 26, 2013 09:38 AM|LINK

  alankarp

  try this

  SELECT ISNULL(Atleta.url_imagem,'no_photo.jpg') as urlimagem, Atleta.id, Atleta.id_categoria, Categoria.nome AS Expr1, Atleta.id_categoria
  FROM Atleta INNER JOIN Categoria ON Atleta.id_categoria = Categoria.id WHERE
  ((? = 0) or (Atleta.id = ?)) and ((? = 0) or (Atleta.id_categoria = ?))
  order by Atleta.nome

  No need to use IIF
  

   

  it givies me syntax error near ?

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  Decker Dong ...

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  Re: check if string is null in sql

  Jan 28, 2013 12:36 AM|LINK

  troika

  it givies me syntax error near ?

  Hi,

  Please use your suitable field or column name propertly instead of "?", because answerer doesn't know you real columnName.

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  troika

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  Re: check if string is null in sql

  Jan 30, 2013 09:42 AM|LINK

  what i need is a querystring thats why i use ?

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  Decker Dong ...

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  Re: check if string is null in sql

  Feb 01, 2013 12:48 AM|LINK

  troika

  what i need is a querystring thats why i use ?

  Please use parameter token and QueryStringParameter, and here's a sample:

  http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.sqldatasource.aspx

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  troika

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  Re: check if string is null in sql

  Feb 07, 2013 01:30 PM|LINK

  i'm using this command to check if is dbnull , but i also need to check if its empty... how can i do that here in image and link eval's

  and also this is not loading the default no_photo image...

  <a href='<%# Eval("photo") == DBNull.Value ? "/images/no_photo.png" : Eval("photo") %>' rel="lightbox[on]" title="+ <a href='<%# Eval("Link") %>'>Info</a>"><asp:Image id="img" runat="server" ImageUrl='<%#Eval("photo", "~/images/uploads/{0}") %>' /> </a>

  • Edited by troika on Feb 07, 2013 01:36 PM
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  Decker Dong ...

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  Re: check if string is null in sql

  Feb 08, 2013 12:08 AM|LINK

  Hi,

  for multiple checkings, I think you can just write down a function to cope with this:

  <a href='<%# MyFunc(Eval("photo"))%>

  And then

  protected string MyFunc(object obj)
  {
   if(obj==null || obj==DbNull.Value)
   return something;
   else if (obj.ToString().Trim()=="")
   return something;
   else
   return obj.ToString();
  }