title: Error converting datatype varchar to numeric in SqlDataAdapter
body: <p>I'm trying to retrieve an amount from SQL.</p>
  
  <p>I have a table <code>tbVendas</code> with a column <code>ValorTotalVendas</code> of datatype <code>DECIMAL</code>.</p>
  
  <p>I have the following select query </p>
  
  <pre><code>SELECT IdVendas AS 'Venda' 
  FROM tbVendas 
  WHERE ValorTotalVendas = '@valorTotal'
  </code></pre>
  
  <p>And below my command </p>
  
  <pre><code>SqlCommand comando = new SqlCommand(strSql, conn);
  comando.Parameters.Add("@valorTotal", SqlDbType.Decimal);
  comando.Parameters["@valorTotal"].Value = Convert.ToDecimal(txbValorFiltro.Text);
  
  DataTable vendas = new DataTable();
  
  conn.Open();
  
  SqlDataAdapter sqdDA = new SqlDataAdapter(strSql, conn);
  sqdDA.Fill(vendas);
  </code></pre>
  
  <p>But I get this error:</p>
  
  <blockquote>
    <p>Error converting datatype varchar to numeric</p>
  </blockquote>
  
  <p>Can anyone please help me?</p>