/// <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.DecorateTable(Schema, 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>
/// Gets the main select clause
/// </summary>
/// <param name="from">The from clause to use (if it is not schema.table)</param>
/// <returns>The plain select clause without any constraints or order clauses</returns>
public string GetSelectClause(string from)
{
if (string.IsNullOrEmpty(from))
{
from = _spatialDbUtility.DecorateTable(_provider.Schema, _provider.Table);
}
if (string.IsNullOrEmpty(_selectClause))
{
var sqlBuilder = new StringBuilder("SELECT ");
sqlBuilder.Append(_spatialDbUtility.DecorateAs(_provider.ObjectIdColumn));
foreach (var fc in this)
{
if (!fc.Display)
{
continue;
}
sqlBuilder.AppendFormat(", {0}", _spatialDbUtility.DecorateAs(
!string.IsNullOrEmpty(fc.Function) ? GetFunctionColumn(fc) : fc.Column,
fc.As));
}
sqlBuilder.AppendFormat(", {0}", GetGeometryColumn(true));
sqlBuilder.AppendFormat(" FROM {0}", from);
_selectClause = sqlBuilder.ToString();
}
return(_selectClause);
}
/// <summary>
/// Method to generate a SQL-From statement for a bounding box query
/// </summary>
/// <param name="envelope">The envelope to query</param>
/// <param name="command">The command object that is supposed to perform the query</param>
/// <returns>A SQL From statement string</returns>
protected virtual string GetFrom(Envelope envelope, DbCommand command)
{
return(_dbUtility.DecorateTable(_schema, _table));
}