/// <summary>
/// Excutes CommandText for read
/// </summary>
/// <param name="propList">
/// Optional:CSV of properies. limits number of Fileds that will be returned in result. it can
/// increase performance.
/// </param>
/// <param name="queryConditions">
/// Optional: Limits rows by condition on fields. Default logic is AND. You can change it in
/// Logic argument of this method
/// </param>
/// <param name="logic">The logic.</param>
/// <returns>A collection of string in raw format of API result.</returns>
public IEnumerable <string> ExecuteReader(string propList = null,
MKCommandParameterCollection queryConditions = null, MKQueryLogicOperators logic = MKQueryLogicOperators.And)
{
verifyConnection();
if (!string.IsNullOrEmpty(propList))
{
Parameters.Add(".proplist", propList);
}
//*******************************************
if (CommandText.Contains(@"/where/"))
{
if (queryConditions == null)
{
queryConditions = new MKCommandParameterCollection();
}
queryConditions.AddRange(getCommandTextQueries(CommandText));
}
if (queryConditions != null)
{
foreach (var q in queryConditions)
{
q.Name = "?" + q.Name;
Parameters.Add(q);
}
if (queryConditions.Count > 1)
{
switch (logic)
{
case MKQueryLogicOperators.And:
Parameters.Add("?#", "&");
break;
case MKQueryLogicOperators.Or:
Parameters.Add("?#", "|");
break;
}
}
}
sendCommand();
var res = Connection.Read();
checkResponse(res);
return(res);
}
private void HandleTempTable()
{
if (!CommandText.Contains(SingleRowTempTableRequiredToken))
{
return;
}
var commandText = CommandText;
var tempFile = Path.Combine(Path.GetDirectoryName(Path.GetFullPath(Connection.DataSource)), SingleRowTempTableName + ".dbf");
if (!File.Exists(tempFile))
{
CommandText = "CREATE TABLE '" + tempFile + "' FREE (PK i)";
ExecuteNonQuery();
CommandText = "INSERT INTO '" + tempFile + "' VALUE(1)";
ExecuteNonQuery();
}
CommandText = commandText.Replace(SingleRowTempTableRequiredToken, "'" + tempFile + "'");
}
protected override DbDataReader ExecuteDbDataReader(CommandBehavior behavior)
{
/*
* SchemaManager (and why here) explained:
*
* From what I can tell, the EF designer is only able to get schema information from querying data using the connection. This seemed to be
* a problem because I couldn't figure a way to get all the required information from a DBC... plus, I really didn't want to require a DBC to use this
* EF Provider. What I figured I could do instead was hook into the query process and use a combination of techniques to get the schema information
* and write it to a temp table. Then rewrite the command text to include the temp table.
*
* The part of the query that needs to be rewritten comes from the DefiningQuery in StoreSchemaDefinition.ssdl. The DefiningQuery will have a token
* that identifies the requested schema information.
*
* This was the only place that I found where I had an instance of the connection and the command...
*
*/
if (SchemaManager.IsSchemaQuery(this.CommandText))
{
DataTable dataTable = null;
SchemaManager.Using(Connection.ConnectionString, (schemaManager) => dataTable = schemaManager.CreateDataTable(CommandText, Parameters));
return(dataTable.CreateDataReader());
}
var hasExecuteScalar = CommandText.Contains(ExecuteScalarBeginDelimiter);
HandleTempTable();
SplitMultipleCommands();
HandleExecuteScalar();
var reader = (VfpClient.VfpDataReader)base.ExecuteDbDataReader(behavior);
if (hasExecuteScalar)
{
return(new VfpAutoIncDataReader(reader, CommandText));
}
return(reader);
}
void ValidateParameters(IEnumerable <DbParameter> parameters)
{
const string errmsg = "Issue found with parameter `{0}` on object `{1}`:{2}{2}{3}";
foreach (var p in parameters)
{
var n = p.ParameterName;
Debug.Assert(n.Length >= 2,
string.Format(errmsg, p, this, Environment.NewLine,
"Parameters should always be 2 or more characters (one for the prefix, one or more for the name)."));
Debug.Assert(n[0] == ParameterPrefixChar,
string.Format(errmsg, p, this, Environment.NewLine, "Parameters should begin with the ParameterPrefix."));
Debug.Assert(n[1] != ParameterPrefixChar,
string.Format(errmsg, p, this, Environment.NewLine, "The second character should not be the ParameterPrefix."));
Debug.Assert(CommandText.Contains(p.ParameterName),
string.Format(errmsg, p, this, Environment.NewLine, "The parameter could not be found in the CommandText..."));
}
}
