/// <summary>
/// Method to get the number of features in the datasource
/// </summary>
/// <returns>The number of features</returns>
protected virtual int GetFeatureCountInternal()
{
using (var conn = CreateOpenDbConnection())
{
using (var command = conn.CreateCommand())
{
var sql = new StringBuilder();
sql.AppendFormat("SELECT COUNT(*) FROM {0}", _dbUtility.DecorateEntity(Table));
#pragma warning disable 612,618
if (!String.IsNullOrEmpty(DefinitionQuery))
{
sql.AppendFormat(" WHERE {0}", DefinitionQuery);
}
#pragma warning restore 612,618
else
{
sql.Append(FeatureColumns.GetWhereClause());
}
sql.Append(";");
command.CommandText = sql.ToString();
return((int)command.ExecuteScalar());
}
}
}
/// <summary>
/// Function to get a specific feature from the database.
/// </summary>
/// <param name="oid">The object id</param>
/// <returns>A feature data row</returns>
protected virtual FeatureDataRow GetFeatureInternal(uint oid)
{
using (var cn = CreateOpenDbConnection())
{
using (var cmd = cn.CreateCommand())
{
cmd.CommandText = FeatureColumns.GetSelectClause(From)
+ string.Format(" WHERE {0}={1};", _dbUtility.DecorateEntity(ObjectIdColumn), oid);
Logger.Debug(t => t("Executing query:\n{0}", PrintCommand(cmd)));
using (var dr = cmd.ExecuteReader())
{
if (dr.HasRows)
{
dr.Read();
var fdt = CreateNewTable();
FeatureDataRow row = null;
fdt.BeginLoadData();
var numColumns = fdt.Columns.Count;
var data = new object[numColumns + 1];
if (dr.GetValues(data) > 0)
{
var loadData = new object[numColumns];
Array.Copy(data, 0, loadData, 0, numColumns);
row = (FeatureDataRow)fdt.LoadDataRow(loadData, true);
row.Geometry = GeometryFromWKB.Parse((byte[])data[numColumns], Factory);
}
fdt.EndLoadData();
return(row);
}
}
}
}
return(null);
}
/// <summary>
/// Gets the SQL ORDER BY clause.
/// </summary>
/// <returns>The order by</returns>
public string GetOrderByClause()
{
var orderBy = string.Empty;
foreach (var featureColumn in Items)
{
switch (featureColumn.OrderBy)
{
case null:
continue;
case "ASC":
orderBy += string.Format(", {0}", _spatialDbUtility.DecorateEntity(featureColumn.As));
break;
case "DESC":
orderBy += string.Format(", {0} DESC", _spatialDbUtility.DecorateEntity(featureColumn.As));
break;
}
}
return(orderBy.Length > 0 ? orderBy.Substring(2) : null);
}
