/// <summary>
/// Get the names of the columns as defined in the database
/// </summary>
/// <returns></returns>
public string[] GetDbFieldNames()
{
string sql = "select Top 1 * from " + TableName;
var reader = MyDataSource.ExecuteReader(sql);
var schemaTable = reader.GetSchemaTable();
MyDataSource.DisposeReader(reader);
return((from dr in schemaTable?.Rows.Cast <DataRow>()
select dr["ColumnName"].ToString()).ToArray());
}
public int[] GetIDs(bool sortByID = false)
{
if (string.IsNullOrEmpty(IDField))
{
return(null);
}
var sql = "select " + IDField + " from " + TableName + (sortByID ? " order by " + IDField + " asc;" : "");
var r = MyDataSource.ExecuteReader(sql);
var result = new List <int>();
while (r.Read())
{
var id = r.GetInt32(0);
result.Add(id);
}
MyDataSource.DisposeReader(r);
return(result.ToArray());
}
public TField[] GetFieldDistinctValues <TField>(string fieldName, bool sort = false)
{
var fi = typeof(T).GetField(fieldName);
if (fi == null)
{
throw new Exception("FieldName doesn't match any public field in type");
}
int fiIndex = _fieldInfos.IndexOf(fi);
var dbFn = _dbFieldNames[fiIndex];
var sql = $"select distinct {dbFn} from {TableName}" + (sort ? $" order by {dbFn} asc;" : "");
var r = MyDataSource.ExecuteReader(sql);
var result = new List <TField>();
while (r.Read())
{
var vO = r[0];
result.Add((TField)vO);
}
MyDataSource.DisposeReader(r);
return(result.ToArray());
}