/// <summary>
/// Deletes a single table in the database
/// </summary>
/// <param name="tableName">Name of the table.</param>
/// <exception cref="EsentObjectNotFoundException">
/// Thrown when the specified table can't be found.
/// </exception>
/// <exception cref="EsentTableInUseException">
/// Thrown when the specified table still has cursors open.
/// </exception>
/// <remarks>
/// It is currently not possible to delete a table that is being used
/// by a Cursor. All such Cursors must be disposed before the
/// table can be successfully deleted.
/// </remarks>
public override void DropTable(string tableName)
{
lock (this.IsamSession)
{
this.CheckDisposed();
if (!this.Exists(tableName))
{
throw new EsentObjectNotFoundException();
}
TempTableHandle tempTableHandle = this.TempTableHandles[tableName];
if (tempTableHandle.CursorCount > 0)
{
throw new EsentTableInUseException();
}
this.Tables.Remove(tableName);
Api.JetCloseTable(this.IsamSession.Sesid, tempTableHandle.Handle);
this.TempTableHandles.Remove(tempTableHandle.Name);
this.IsamSession.IsamInstance.TempTableHandles.Remove(tempTableHandle.Guid.ToString());
}
}
/// <summary>
/// Releases the temporary table.
/// </summary>
/// <param name="tableName">Name of the table.</param>
/// <param name="inInsertMode">if set to <c>true</c> [in insert mode].</param>
internal void ReleaseTempTable(string tableName, bool inInsertMode)
{
lock (this.IsamSession)
{
TempTableHandle tempTableHandle = this.TempTableHandles[tableName];
tempTableHandle.InInsertMode = inInsertMode;
tempTableHandle.CursorCount--;
}
}
/// <summary>
/// Adds the specified temporary table handle.
/// </summary>
/// <param name="tempTableHandle">The temporary table handle.</param>
public void Add(TempTableHandle tempTableHandle)
{
if (this.isKeyGuid)
{
this.Dictionary.Add(tempTableHandle.Guid.ToString().ToLower(CultureInfo.InvariantCulture), tempTableHandle);
}
else
{
this.Dictionary.Add(tempTableHandle.Name.ToLower(CultureInfo.InvariantCulture), tempTableHandle);
}
}
/// <summary>
/// Opens a cursor over the specified table.
/// </summary>
/// <param name="tableName">the name of the table to be opened</param>
/// <returns>a cursor over the specified table in this database</returns>
public override Cursor OpenCursor(string tableName)
{
lock (this.IsamSession)
{
this.CheckDisposed();
if (!this.Exists(tableName))
{
throw new EsentObjectNotFoundException();
}
TableDefinition tableDefinition = this.Tables[tableName];
TempTableHandle tempTableHandle = this.TempTableHandles[tableName];
JET_TABLEID tableid;
try
{
// if this is a Sort then we must always fail to dup the
// cursor
//
// NOTE: this is a hack to work around problems in ESE/ESENT
// that we cannot fix because we must work downlevel
if (tableDefinition.Type == TableType.Sort)
{
throw new EsentIllegalOperationException();
}
Api.JetDupCursor(this.IsamSession.Sesid, tempTableHandle.Handle, out tableid, DupCursorGrbit.None);
tempTableHandle.InInsertMode = false;
}
catch (EsentIllegalOperationException)
{
if (tempTableHandle.CursorCount > 0)
{
throw new InvalidOperationException("It is not possible to have multiple open cursors on a temporary table that is currently in insert mode.");
}
else
{
tableid = tempTableHandle.Handle;
}
}
Cursor newCursor = new Cursor(this.IsamSession, this, tableName, tableid, tempTableHandle.InInsertMode);
tempTableHandle.CursorCount++;
return(newCursor);
}
}
/// <summary>
/// Adds the specified temporary table handle.
/// </summary>
/// <param name="tempTableHandle">The temporary table handle.</param>
public void Add(TempTableHandle tempTableHandle)
{
if (this.isKeyGuid)
{
this.Dictionary.Add(tempTableHandle.Guid.ToString().ToLower(CultureInfo.InvariantCulture), tempTableHandle);
}
else
{
this.Dictionary.Add(tempTableHandle.Name.ToLower(CultureInfo.InvariantCulture), tempTableHandle);
}
}
/// <summary>
/// Creates a single table with the specified definition in the database
/// </summary>
/// <param name="tableDefinition">The table definition.</param>
/// <exception cref="EsentTableDuplicateException">
/// Thrown when the table definition overlaps with an already existing table.
/// </exception>
/// <exception cref="System.ArgumentException">A MaxKeyLength > 255 is not supported for indices over a temporary table on this version of the database engine.;tableDefinition</exception>
public override void CreateTable(TableDefinition tableDefinition)
{
lock (this.IsamSession)
{
this.CheckDisposed();
// validate the table definition for creating a TT
this.ValidateTableDefinition(tableDefinition);
// convert the given table definition into an JET_OPENTEMPORARYTABLE
// struct that we will use to create the TT
JET_OPENTEMPORARYTABLE openTemporaryTable = this.MakeOpenTemporaryTable(tableDefinition);
// check if the TT already exists
if (this.Exists(tableDefinition.Name))
{
throw new EsentTableDuplicateException();
}
// do not allow the TT to be created if the session is in a
// transaction. we disallow this to sidestep the problem where
// JET will automatically close (and destroy) the TT if the
// current level of the transaction is aborted
if (this.IsamSession.TransactionLevel > 0)
{
// NOTE: i'm thinking that this requirement is pretty lame,
// especially since it only hits us on an abort. I am going
// to allow this for now and see what happens
// throw new ArgumentException( "We do not currently allow you to create temp tables while inside of a transaction." );
}
// create the TT
JET_TABLEID tableid = new JET_TABLEID();
if (DatabaseCommon.CheckEngineVersion(
this.IsamSession,
DatabaseCommon.ESENTVersion(6, 0, 6000, 0),
DatabaseCommon.ESEVersion(8, 0, 685, 0)))
{
VistaApi.JetOpenTemporaryTable(this.IsamSession.Sesid, openTemporaryTable);
tableid = openTemporaryTable.tableid;
}
else
{
if (openTemporaryTable.cbKeyMost > 255)
{
throw new ArgumentException("A MaxKeyLength > 255 is not supported for indices over a temporary table on this version of the database engine.", "tableDefinition");
}
Api.JetOpenTempTable2(
this.IsamSession.Sesid,
openTemporaryTable.prgcolumndef,
openTemporaryTable.prgcolumndef.Length,
openTemporaryTable.pidxunicode.lcid,
openTemporaryTable.grbit,
out tableid,
openTemporaryTable.prgcolumnid);
}
// re-create the TT's schema to reflect the created TT
TableDefinition tableDefinitionToCache = MakeTableDefinitionToCache(tableDefinition, openTemporaryTable);
// cache the TT and its handle
TempTableHandle tempTableHandle = new TempTableHandle(
tableDefinitionToCache.Name,
this.IsamSession.Sesid,
tableid,
tableDefinitionToCache.Type == TableType.Sort || tableDefinitionToCache.Type == TableType.PreSortTemporary);
this.Tables.Add(tableDefinitionToCache);
this.TempTableHandles.Add(tempTableHandle);
this.IsamSession.IsamInstance.TempTableHandles.Add(tempTableHandle);
}
}
