Is there a standard approach to generating sql dynamically?

sqlCmd.CommandText = "DECLARE @t Table(ContactId int, ROWRANK int" + declare
      + ")INSERT INTO @t(ContactId, ROWRANK" + insertFields + ")"//Insert as few cols a possible
      + "Select ContactID, ROW_NUMBER() OVER (ORDER BY " + sortExpression + " "
      + sortDirection + ") as ROWRANK" // generates a rowrank for each row
      + outerFields
      + " FROM ( SELECT c.id AS ContactID"
      + coreFields
      + from         // sometimes different tables are required
      + where + ") T " // user input goes here.
      + groupBy+ " "
      + havingClause //can be empty
      + ";"
      + "select @@rowcount as rCount;" // return 2 recordsets, avoids second query
      + " SELECT " + fields + ",field1,field2" // join onto the other cols n the table
      +" FROM @t t INNER JOIN contacts c on t.ContactID = c.id"
      +" WHERE ROWRANK BETWEEN " + ((pageIndex * pageSize) + 1) + " AND "
      + ( (pageIndex + 1) * pageSize); // here I select the pages I want

//Add Parameter to SQL Command
AddParamToSQLCmd(sqlCmd, "@p" + z.ToString(), SqlDbType.VarChar, 50, ParameterDirection.Input, qc.FieldValue);
// Create SQL code Fragment
where.AppendFormat(" {0} {1} {2} @p{3}", qc.BooleanOperator, qc.FieldName, qc.ComparisonOperator, z);

string query= "SELECT {0} FROM .... WHERE {1}"
StringBuilder selectclause = new StringBuilder();
StringBuilder wherecaluse = new StringBuilder();

// .... the logic here will vary greatly depending on what your system looks like

MySqlcommand.CommandText = String.Format(query, selectclause.ToString(), whereclause.ToString());

List<Expression> expressions = new List<Expression>(userConditions.Count);
foreach(Condition c in userConditions)
{
    expressions.Add(Expression.Eq(c.Field, c.Value));
}
SomeTable[] records = SomeTable.Find(expressions);

where...
and (@MyParam5 is null or @MyParam5 = Col5)