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POWhat is the best way to implement a search in the pattern DAL?
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  1. POWhat is the best way to implement a search in the pattern DAL?
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    copied!<p>I usually declare my DAL classes overwriting search methods whenever possible as the example below:</p> <pre><code>public class clsAsd { private AdConn oConn; public clsAsd(ref AdConn Connection) { oConn = Connection; } private string sqlSearch(string DocType, string Status, string Aaa) { return " AND x.tp_doc = '" + DocType + "'\r\n" + " AND x.co_status IN (" + Status + ")\r\n" + " AND x.aaa = '" + Aaa + "'\r\n"; } public List&lt;clsQwe&gt; search(string DocType, string Status, string Aaa, bool IncDel) { return search(sqlSearch(DocType, Status, Aaa), IncDel); } private string sqlSearch(string DocType, string Status, string Aaa, string Bbb) { string sSQL = sqlSearch(DocType, Status, Aaa) + (Bbb != "" ? " AND x.bbb = '" + Bbb + "'\r\n" : ""); return sSQL; } public List&lt;clsQwe&gt; search(string DocType, string Status, string Aaa, string Bbb, bool IncDel) { return search(sqlSearch(DocType, Status, Aaa, Bbb), IncDel); } private List&lt;clsQwe&gt; search(string Where, bool IncDel) { string sSQL; sSQL = "SELECT\r\n"; sSQL += " b.aaa, c.bbb, x.*\r\n"; sSQL += "FROM asd x, qwe b, zxc c\r\n"; sSQL += "WHERE x.www = b.www\r\n"; sSQL += " AND x.zzz = c.zzz\r\n"; sSQL += Where; if (!IncDel) sSQL += " AND x.del IS NULL\r\n"; sSQL += "ORDER BY x.www"; // Connection + Run SQL // List to get results List&lt;clsQwe&gt; lstRet = new List&lt;clsQwe&gt;(); // Row to add in list clsQwe oX; while (oReader.Read()) { oX = new clsQwe(); // Add all data lstRet.Add(oX); } // Return data return lstRet; } } </code></pre> <p>My question is: is this a good practice?</p> <p>I should use one method for each different search? example:</p> <pre><code>public class clsAsd { private AdConn oConn; public clsAsd(ref AdConn Connection) { oConn = Connection; } public List&lt;clsQwe&gt; search1(string DocType, string Status, string Aaa, bool IncDel) { } public List&lt;clsQwe&gt; search2(string DocType, string Status, string Aaa, string Bbb, bool IncDel) { } public List&lt;clsQwe&gt; search3(string DocType, string Status, string Aaa, string Bbb, string Ccc, bool IncDel) { } private List&lt;clsQwe&gt; search(string Where, bool IncDel) { } } </code></pre> <p>How could I improve this class?</p> <p>I'm considering implementing only one search method that receives the class (clsQwe) as a parameter. I check each property of this class and create the where clause in accordance with properties populated.</p> <p>This approach is interesting?</p> <p>Thank you.</p>
 

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