/// <summary>
/// Clones this instance.
/// </summary>
/// <returns>The created object</returns>
object ICloneable.Clone()
{
JetCommand clone = new JetCommand();
clone._Connection = this._Connection;
clone._WrappedCommand = (DbCommand)((ICloneable)this._WrappedCommand).Clone();
return(clone);
}
public DbCommand CreateCommand(string commandText, int?commandTimeout = null)
{
if (string.IsNullOrEmpty(commandText))
{
// SqlCommand will complain if the command text is empty
commandText = Environment.NewLine;
}
var command = new JetCommand(commandText, this);
if (commandTimeout.HasValue)
{
command.CommandTimeout = commandTimeout.Value;
}
return(command);
}
/// <summary>
/// Create a DbCommand object, given the provider manifest and command tree
/// </summary>
private DbCommand CreateCommand(DbProviderManifest manifest, DbCommandTree commandTree)
{
if (manifest == null)
{
throw new ArgumentNullException("manifest");
}
if (commandTree == null)
{
throw new ArgumentNullException("commandTree");
}
JetProviderManifest jetManifest = (manifest as JetProviderManifest);
if (jetManifest == null)
{
throw new ArgumentException("The provider manifest given is not of type 'JetProviderManifest'.");
}
JetCommand command = new JetCommand();
List <DbParameter> parameters;
CommandType commandType;
command.CommandText = SqlGenerator.GenerateSql(commandTree, out parameters, out commandType);
command.CommandType = commandType;
//if (command.CommandType == CommandType.Text)
// command.CommandText += Environment.NewLine + Environment.NewLine + "-- provider: " + this.GetType().Assembly.FullName;
// Get the function (if any) implemented by the command tree since this influences our interpretation of parameters
EdmFunction function = null;
if (commandTree is DbFunctionCommandTree)
{
function = ((DbFunctionCommandTree)commandTree).EdmFunction;
}
// Now make sure we populate the command's parameters from the CQT's parameters:
foreach (KeyValuePair <string, TypeUsage> queryParameter in commandTree.Parameters)
{
OleDbParameter parameter;
// Use the corresponding function parameter TypeUsage where available (currently, the SSDL facets and
// type trump user-defined facets and type in the EntityCommand).
FunctionParameter functionParameter;
if (function != null && function.Parameters.TryGetValue(queryParameter.Key, false, out functionParameter))
{
parameter = CreateJetParameter(functionParameter.Name, functionParameter.TypeUsage, functionParameter.Mode, DBNull.Value);
}
else
{
parameter = CreateJetParameter(queryParameter.Key, queryParameter.Value, ParameterMode.In, DBNull.Value);
}
command.Parameters.Add(parameter);
}
// Now add parameters added as part of SQL gen (note: this feature is only safe for DML SQL gen which
// does not support user parameters, where there is no risk of name collision)
if (parameters != null && parameters.Count > 0)
{
if (!(commandTree is DbInsertCommandTree) &&
!(commandTree is DbUpdateCommandTree) &&
!(commandTree is DbDeleteCommandTree))
{
throw new InvalidOperationException("SqlGenParametersNotPermitted");
}
foreach (DbParameter parameter in parameters)
{
command.Parameters.Add(parameter);
}
}
return(command);
}