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copied!<p>Use <a href="http://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqlcommand.executereader.aspx" rel="noreferrer"><code>ExecuteReader()</code></a> and not <a href="http://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqlcommand.executenonquery.aspx" rel="noreferrer"><code>ExecuteNonQuery()</code></a>. <code>ExecuteNonQuery()</code> returns only the number of rows affected.</p> <pre><code>try { SqlDataReader dr = cmd1.ExecuteReader(); } catch (SqlException oError) { } while(dr.Read()) { string treatment = dr[0].ToString(); } </code></pre> <p>Or better, use a <a href="https://msdn.microsoft.com/en-us/library/yh598w02.aspx" rel="noreferrer"><code>using</code> statement</a> for it.</p> <pre><code>using(SqlDataReader dr = cmd1.ExecuteReader()) { while(dr.Read()) { string treatment = dr[0].ToString(); } } </code></pre> <p>But if your <code>SqlCommand</code> returns only <code>1</code> column, you can use the <a href="http://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqlcommand.executescalar.aspx" rel="noreferrer"><code>ExecuteScalar()</code></a> method. It returns first column of the first row as follows:-</p> <pre><code>cmd.CommandText = "SELECT treatment FROM appointment WHERE patientid = " + text; string str = Convert.ToString(cmd.ExecuteScalar()); </code></pre> <p>Also you can open your code to <a href="http://en.wikipedia.org/wiki/SQL_injection" rel="noreferrer">SQL Injection</a>. Always use parameterized queries. Jeff has a cool blog article called <a href="http://www.codinghorror.com/blog/2005/04/give-me-parameterized-sql-or-give-me-death.html" rel="noreferrer">Give me parameterized SQL, or give me death</a>. Please read it carefully. Also read <a href="http://www.dotnetperls.com/sqlparameter" rel="noreferrer">DotNetPerl SqlParameter</a> article. SQL Injection very important when you are working queries.</p>

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