/// <summary>
/// Creates and attaches a database file.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="database">The path to the database file to create.</param>
/// <param name="dbid">Returns the dbid of the new database.</param>
/// <param name="grbit">Database creation options.</param>
public static void CreateDatabase(JET_SESID sesid, string database, out JET_DBID dbid, CreateDatabaseGrbit grbit)
{
Api.JetCreateDatabase(sesid, database, null, out dbid, grbit);
}
/// <summary>
/// Position the cursor before the first record in the table. A
/// subsequent move next will position the cursor on the first
/// record.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The table to position.</param>
public static void MoveBeforeFirst(JET_SESID sesid, JET_TABLEID tableid)
{
Api.TryMoveFirst(sesid, tableid);
Api.TryMovePrevious(sesid, tableid);
}
/// <summary>
/// Try to move to the next record in the table. If there is not a next record
/// this returns false, if a different error is encountered an exception is thrown.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The cursor to position.</param>
/// <returns>True if the move was successful.</returns>
public static bool TryMoveNext(JET_SESID sesid, JET_TABLEID tableid)
{
return(TryMove(sesid, tableid, JET_Move.Next, MoveGrbit.None));
}
/// <summary>
/// Initializes a new instance of the InstanceParameters class.
/// </summary>
/// <param name="instance">The instance to set parameters on.</param>
public InstanceParameters(JET_INSTANCE instance)
{
this.instance = instance;
this.sesid = JET_SESID.Nil;
}
/// <summary>
/// Initializes a new instance of the Transaction class. This automatically
/// begins a transaction. The transaction will be rolled back if
/// not explicitly committed.
/// </summary>
/// <param name="sesid">The session to start the transaction for.</param>
public Transaction(JET_SESID sesid)
{
this.sesid = sesid;
this.Begin();
}
public static ulong?RetrieveColumnAsUInt64(JET_SESID sesid, JET_TABLEID tableid, JET_COLUMNID columnid)
{
return(RetrieveColumnAsUInt64(sesid, tableid, columnid, RetrieveColumnGrbit.None));
}
/// <summary>
/// Constructs a search key that may then be used by <see cref="JetSeek"/>
/// and <see cref="JetSetIndexRange"/>.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The cursor to create the key on.</param>
/// <param name="data">Column data for the current key column of the current index.</param>
/// <param name="grbit">Key options.</param>
public static void MakeKey(JET_SESID sesid, JET_TABLEID tableid, bool data, MakeKeyGrbit grbit)
{
byte b = data ? (byte)0xff : (byte)0x0;
Api.MakeKey(sesid, tableid, b, grbit);
}
/// <summary>
/// Modifies a single column value in a modified record to be inserted or to
/// update the current record.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The cursor to update. An update should be prepared.</param>
/// <param name="columnid">The columnid to set.</param>
/// <param name="data">The data to set.</param>
public static void SetColumn(JET_SESID sesid, JET_TABLEID tableid, JET_COLUMNID columnid, byte[] data)
{
SetColumn(sesid, tableid, columnid, data, SetColumnGrbit.None);
}
/// <summary>
/// Modifies a single column value in a modified record to be inserted or to
/// update the current record.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The cursor to update. An update should be prepared.</param>
/// <param name="columnid">The columnid to set.</param>
/// <param name="data">The data to set.</param>
public static void SetColumn(JET_SESID sesid, JET_TABLEID tableid, JET_COLUMNID columnid, bool data)
{
byte b = data ? (byte)0xff : (byte)0x0;
SetColumn(sesid, tableid, columnid, b);
}
/// <summary> /// Recursive SetColumns method for data pinning. This should populate the buffer and /// call the inherited SetColumns method. /// </summary> /// <param name="sesid">The session to use.</param> /// <param name="tableid"> /// The table to set the columns in. An update should be prepared. /// </param> /// <param name="columnValues"> /// Column values to set. /// </param> /// <param name="nativeColumns"> /// Structures to put the pinned data in. /// </param> /// <param name="i">Offset of this object in the array.</param> /// <returns>An error code.</returns> internal abstract unsafe int SetColumns(JET_SESID sesid, JET_TABLEID tableid, ColumnValue[] columnValues, NATIVE_SETCOLUMN *nativeColumns, int i);
/// <summary>
/// Initializes a new instance of the <see cref="TableEnumerator{T}"/> class.
/// </summary>
/// <param name="sesid">
/// The session to use.
/// </param>
protected TableEnumerator(JET_SESID sesid)
{
this.Sesid = sesid;
this.TableidToEnumerate = JET_TABLEID.Nil;
}
/// <summary>
/// Recursive RetrieveColumns method for data pinning. This should pin a buffer and
/// call the inherited RetrieveColumns method.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">
/// The table to retrieve the columns from.
/// </param>
/// <param name="columnValues">
/// Column values to retrieve.
/// </param>
internal static void RetrieveColumns(JET_SESID sesid, JET_TABLEID tableid, ColumnValue[] columnValues)
{
const int MaxColumnValues = 1024;
if (columnValues.Length > MaxColumnValues)
{
throw new ArgumentOutOfRangeException("columnValues", columnValues.Length, "Too many column values");
}
unsafe
{
byte[] buffer = null;
NATIVE_RETRIEVECOLUMN *nativeRetrievecolumns = stackalloc NATIVE_RETRIEVECOLUMN[columnValues.Length];
try
{
buffer = Caches.ColumnCache.Allocate();
Debug.Assert(MaxColumnValues * 16 < buffer.Length, "Maximum size of fixed columns could exceed buffer size");
fixed(byte *pinnedBuffer = buffer)
{
byte *currentBuffer = pinnedBuffer;
int numVariableLengthColumns = columnValues.Length;
// First the fixed-size columns
for (int i = 0; i < columnValues.Length; ++i)
{
if (0 != columnValues[i].Size)
{
columnValues[i].MakeNativeRetrieveColumn(ref nativeRetrievecolumns[i]);
nativeRetrievecolumns[i].pvData = new IntPtr(currentBuffer);
nativeRetrievecolumns[i].cbData = checked ((uint)columnValues[i].Size);
currentBuffer += nativeRetrievecolumns[i].cbData;
Debug.Assert(currentBuffer <= pinnedBuffer + buffer.Length, "Moved past end of pinned buffer");
numVariableLengthColumns--;
}
}
// Now the variable-length columns
if (numVariableLengthColumns > 0)
{
int bufferUsed = checked ((int)(currentBuffer - pinnedBuffer));
int bufferRemaining = checked (buffer.Length - bufferUsed);
int bufferPerColumn = bufferRemaining / numVariableLengthColumns;
Debug.Assert(bufferPerColumn > 0, "Not enough buffer left to retrieve variable length columns");
// Now the variable-size columns
for (int i = 0; i < columnValues.Length; ++i)
{
if (0 == columnValues[i].Size)
{
columnValues[i].MakeNativeRetrieveColumn(ref nativeRetrievecolumns[i]);
nativeRetrievecolumns[i].pvData = new IntPtr(currentBuffer);
nativeRetrievecolumns[i].cbData = checked ((uint)bufferPerColumn);
currentBuffer += nativeRetrievecolumns[i].cbData;
Debug.Assert(currentBuffer <= pinnedBuffer + buffer.Length, "Moved past end of pinned buffer");
}
}
}
// Retrieve the columns
Api.Check(Api.Impl.JetRetrieveColumns(sesid, tableid, nativeRetrievecolumns, columnValues.Length));
// Propagate the warnings and output.
for (int i = 0; i < columnValues.Length; ++i)
{
columnValues[i].Error = (JET_wrn)nativeRetrievecolumns[i].err;
columnValues[i].ItagSequence = (int)nativeRetrievecolumns[i].itagSequence;
}
// Now parse out the columns that were retrieved successfully
for (int i = 0; i < columnValues.Length; ++i)
{
if (nativeRetrievecolumns[i].err != (int)JET_wrn.BufferTruncated)
{
byte *columnBuffer = (byte *)nativeRetrievecolumns[i].pvData;
int startIndex = checked ((int)(columnBuffer - pinnedBuffer));
columnValues[i].GetValueFromBytes(
buffer,
startIndex,
checked ((int)nativeRetrievecolumns[i].cbActual),
nativeRetrievecolumns[i].err);
}
}
}
// Finally retrieve the buffers where the columns weren't large enough.
RetrieveTruncatedBuffers(sesid, tableid, columnValues, nativeRetrievecolumns);
}
finally
{
if (buffer != null)
{
Caches.ColumnCache.Free(ref buffer);
}
}
}
}
/// <summary>
/// Modifies a single column value in a modified record to be inserted or to
/// update the current record.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The cursor to update. An update should be prepared.</param>
/// <param name="columnid">The columnid to set.</param>
/// <param name="data">The data to set.</param>
/// <param name="encoding">The encoding used to convert the string.</param>
/// <param name="grbit">SetColumn options.</param>
public static void SetColumn(
JET_SESID sesid, JET_TABLEID tableid, JET_COLUMNID columnid, string data, Encoding encoding, SetColumnGrbit grbit)
{
CheckEncodingIsValid(encoding);
if (null == data)
{
JetSetColumn(sesid, tableid, columnid, null, 0, grbit, null);
}
else if (0 == data.Length)
{
JetSetColumn(sesid, tableid, columnid, null, 0, grbit | SetColumnGrbit.ZeroLength, null);
}
else if (Encoding.Unicode == encoding)
{
// Optimization for setting Unicode strings.
unsafe
{
fixed(char *buffer = data)
{
JetSetColumn(
sesid,
tableid,
columnid,
new IntPtr(buffer),
checked (data.Length * sizeof(char)),
grbit,
null);
}
}
}
else if (encoding.GetMaxByteCount(data.Length) <= Caches.ColumnCache.BufferSize)
{
#if MANAGEDESENT_ON_WSA
// Encoding.GetBytes(char*, int, byte*, int) overload is missing in new Windows UI.
// So we can't use the ColumnCache. We'll just use a different GetBytes() overload.
byte[] buffer = encoding.GetBytes(data);
unsafe
{
fixed(byte *bytes = buffer)
{
JetSetColumn(sesid, tableid, columnid, new IntPtr(bytes), buffer.Length, grbit, null);
}
}
#else
// The encoding output will fix in a cached buffer. Get one to avoid
// more memory allocations.
byte[] buffer = null;
try
{
buffer = Caches.ColumnCache.Allocate();
unsafe
{
fixed(char *chars = data)
fixed(byte *bytes = buffer)
{
int dataSize = encoding.GetBytes(chars, data.Length, bytes, buffer.Length);
JetSetColumn(sesid, tableid, columnid, new IntPtr(bytes), dataSize, grbit, null);
}
}
}
finally
{
if (buffer != null)
{
Caches.ColumnCache.Free(ref buffer);
}
}
#endif
}
else
{
byte[] bytes = encoding.GetBytes(data);
JetSetColumn(sesid, tableid, columnid, bytes, bytes.Length, grbit, null);
}
}
/// <summary>
/// Initializes a new instance of the <see cref="ColumnInfoEnumerator"/> class.
/// </summary>
/// <param name="sesid">
/// The session to use.
/// </param>
protected ColumnInfoEnumerator(JET_SESID sesid) : base(sesid)
{
}
/// <summary>
/// Retrieves a guid column value from the current record. The record is that
/// record associated with the index entry at the current position of the cursor.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The cursor to retrieve the column from.</param>
/// <param name="columnid">The columnid to retrieve.</param>
/// <returns>The data retrieved from the column as a guid. Null if the column is null.</returns>
public static Guid?RetrieveColumnAsGuid(JET_SESID sesid, JET_TABLEID tableid, JET_COLUMNID columnid)
{
return(RetrieveColumnAsGuid(sesid, tableid, columnid, RetrieveColumnGrbit.None));
}
/// <summary>
/// Modifies a single column value in a modified record to be inserted or to
/// update the current record.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The cursor to update. An update should be prepared.</param>
/// <param name="columnid">The columnid to set.</param>
/// <param name="data">The data to set.</param>
public static void SetColumn(JET_SESID sesid, JET_TABLEID tableid, JET_COLUMNID columnid, DateTime data)
{
SetColumn(sesid, tableid, columnid, data.ToOADate());
}
/// <summary>
/// Retrieves a datetime column value from the current record. The record is that
/// record associated with the index entry at the current position of the cursor.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The cursor to retrieve the column from.</param>
/// <param name="columnid">The columnid to retrieve.</param>
/// <returns>The data retrieved from the column as a datetime. Null if the column is null.</returns>
public static DateTime?RetrieveColumnAsDateTime(JET_SESID sesid, JET_TABLEID tableid, JET_COLUMNID columnid)
{
return(RetrieveColumnAsDateTime(sesid, tableid, columnid, RetrieveColumnGrbit.None));
}
/// <summary>
/// Modifies a single column value in a modified record to be inserted or to
/// update the current record.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The cursor to update. An update should be prepared.</param>
/// <param name="columnid">The columnid to set.</param>
/// <param name="data">The data to set.</param>
/// <param name="encoding">The encoding used to convert the string.</param>
public static void SetColumn(
JET_SESID sesid, JET_TABLEID tableid, JET_COLUMNID columnid, string data, Encoding encoding)
{
SetColumn(sesid, tableid, columnid, data, encoding, SetColumnGrbit.None);
}
/// <summary>
/// Deserialize an object from a column.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The table to read from.</param>
/// <param name="columnid">The column to read from.</param>
/// <returns>The deserialized object. Null if the column was null.</returns>
public static object DeserializeObjectFromColumn(JET_SESID sesid, JET_TABLEID tableid, JET_COLUMNID columnid)
{
return(DeserializeObjectFromColumn(sesid, tableid, columnid, RetrieveColumnGrbit.None));
}
/// <summary>
/// Retrieves the size of a single column value from the current record.
/// The record is that record associated with the index entry at the
/// current position of the cursor. Alternatively, this function can
/// retrieve a column from a record being created in the cursor copy
/// buffer. This function can also retrieve column data from an index
/// entry that references the current record.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The cursor to retrieve the column from.</param>
/// <param name="columnid">The columnid to retrieve.</param>
/// <returns>The size of the column. 0 if the column is null.</returns>
public static int?RetrieveColumnSize(JET_SESID sesid, JET_TABLEID tableid, JET_COLUMNID columnid)
{
return(RetrieveColumnSize(sesid, tableid, columnid, 1, RetrieveColumnGrbit.None));
}
/// <summary>
/// Constructs a search key that may then be used by <see cref="JetSeek"/>
/// and <see cref="JetSetIndexRange"/>.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The cursor to create the key on.</param>
/// <param name="data">Column data for the current key column of the current index.</param>
/// <param name="grbit">Key options.</param>
public static void MakeKey(JET_SESID sesid, JET_TABLEID tableid, DateTime data, MakeKeyGrbit grbit)
{
Api.MakeKey(sesid, tableid, data.ToOADate(), grbit);
}
/// <summary>
/// Retrieves a single column value from the current record. The record is that
/// record associated with the index entry at the current position of the cursor.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The cursor to retrieve the column from.</param>
/// <param name="columnid">The columnid to retrieve.</param>
/// <returns>The data retrieved from the column. Null if the column is null.</returns>
public static byte[] RetrieveColumn(JET_SESID sesid, JET_TABLEID tableid, JET_COLUMNID columnid)
{
return(RetrieveColumn(sesid, tableid, columnid, RetrieveColumnGrbit.None, null));
}
/// <summary>
/// Initializes a new instance of the <see cref="TableNameEnumerator"/> class.
/// </summary>
/// <param name="sesid">
/// The session to use.
/// </param>
/// <param name="dbid">
/// The database to get the table names from.
/// </param>
public TableNameEnumerator(JET_SESID sesid, JET_DBID dbid) : base(sesid)
{
this.dbid = dbid;
}
/// <summary>
/// Retrieves a string column value from the current record. The record is that
/// record associated with the index entry at the current position of the cursor.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The cursor to retrieve the column from.</param>
/// <param name="columnid">The columnid to retrieve.</param>
/// <param name="encoding">The string encoding to use when converting data.</param>
/// <returns>The data retrieved from the column as a string. Null if the column is null.</returns>
public static string RetrieveColumnAsString(
JET_SESID sesid, JET_TABLEID tableid, JET_COLUMNID columnid, Encoding encoding)
{
return(RetrieveColumnAsString(sesid, tableid, columnid, encoding, RetrieveColumnGrbit.None));
}
/// <summary>
/// Try to move to the previous record in the table. If there is not a previous record
/// this returns false, if a different error is encountered an exception is thrown.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The cursor to position.</param>
/// <returns>True if the move was successful.</returns>
public static bool TryMovePrevious(JET_SESID sesid, JET_TABLEID tableid)
{
return(TryMove(sesid, tableid, JET_Move.Previous, MoveGrbit.None));
}
/// <summary>
/// Retrieves a string column value from the current record. The record is that
/// record associated with the index entry at the current position of the cursor.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The cursor to retrieve the column from.</param>
/// <param name="columnid">The columnid to retrieve.</param>
/// <param name="encoding">The string encoding to use when converting data.</param>
/// <param name="grbit">Retrieval options.</param>
/// <returns>The data retrieved from the column as a string. Null if the column is null.</returns>
public static string RetrieveColumnAsString(
JET_SESID sesid, JET_TABLEID tableid, JET_COLUMNID columnid, Encoding encoding, RetrieveColumnGrbit grbit)
{
JET_wrn wrn;
// This is an optimization for retrieving small Unicode strings
// We use a stack-allocated buffer to retrieve the data and then create
// a string from the data
if (Encoding.Unicode == encoding)
{
unsafe
{
// 512 bytes give 256 Unicode characters.
const int BufferSize = 512;
char * buffer = stackalloc char[BufferSize];
int actualDataSize;
wrn = JetRetrieveColumn(
sesid, tableid, columnid, new IntPtr(buffer), BufferSize, out actualDataSize, grbit, null);
if (JET_wrn.ColumnNull == wrn)
{
return(null);
}
if (JET_wrn.Success == wrn)
{
return(new string(buffer, 0, actualDataSize / sizeof(char)));
}
Debug.Assert(JET_wrn.BufferTruncated == wrn, "Unexpected warning code");
// Fallthrough to normal case below
}
}
// Retrieving a string happens in two stages: first the data is retrieved into a data
// buffer and then the buffer is converted to a string. The buffer isn't needed for
// very long so we try to use a cached buffer.
byte[] cachedBuffer = memoryCache.Allocate();
byte[] data = cachedBuffer;
int dataSize;
wrn = JetRetrieveColumn(sesid, tableid, columnid, data, data.Length, out dataSize, grbit, null);
if (JET_wrn.ColumnNull == wrn)
{
return(null);
}
if (JET_wrn.BufferTruncated == wrn)
{
Debug.Assert(dataSize > data.Length, "Expected column to be bigger than buffer");
data = new byte[dataSize];
wrn = JetRetrieveColumn(sesid, tableid, columnid, data, data.Length, out dataSize, grbit, null);
if (JET_wrn.BufferTruncated == wrn)
{
string error = String.Format(
CultureInfo.CurrentCulture,
"Column size changed from {0} to {1}. The record was probably updated by another thread.",
data.Length,
dataSize);
Trace.TraceError(error);
throw new InvalidOperationException(error);
}
}
// TODO: for Unicode strings pin the buffer and use the String(char*) constructor.
string s = encoding.GetString(data, 0, dataSize);
// Now we have extracted the string from the buffer we can free (cache) the buffer.
memoryCache.Free(cachedBuffer);
return(s);
}
/// <summary>
/// Position the cursor after the last record in the table. A
/// subsequent move previous will position the cursor on the
/// last record.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The table to position.</param>
public static void MoveAfterLast(JET_SESID sesid, JET_TABLEID tableid)
{
Api.TryMoveLast(sesid, tableid);
Api.TryMoveNext(sesid, tableid);
}
/// <summary>
/// Retrieves a boolean column value from the current record. The record is that
/// record associated with the index entry at the current position of the cursor.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The cursor to retrieve the column from.</param>
/// <param name="columnid">The columnid to retrieve.</param>
/// <returns>The data retrieved from the column as a boolean. Null if the column is null.</returns>
public static bool?RetrieveColumnAsBoolean(JET_SESID sesid, JET_TABLEID tableid, JET_COLUMNID columnid)
{
return(RetrieveColumnAsBoolean(sesid, tableid, columnid, RetrieveColumnGrbit.None));
}
/// <summary>
/// Recursive SetColumns method for data pinning. This populates the buffer and
/// calls the inherited SetColumns method.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">
/// The table to set the columns in. An update should be prepared.
/// </param>
/// <param name="columnValues">
/// Column values to set.
/// </param>
/// <param name="nativeColumns">
/// Structures to put the pinned data in.
/// </param>
/// <param name="i">Offset of this object in the array.</param>
/// <returns>An error code.</returns>
internal override unsafe int SetColumns(JET_SESID sesid, JET_TABLEID tableid, ColumnValue[] columnValues, NATIVE_SETCOLUMN *nativeColumns, int i)
{
var data = this.Value.GetValueOrDefault();
return(this.SetColumns(sesid, tableid, columnValues, nativeColumns, i, &data, sizeof(byte), this.Value.HasValue));
}
/// <summary>
/// Initialize a new ESENT session.
/// </summary>
/// <param name="instance">The initialized instance to create the session in.</param>
/// <param name="sesid">Returns the created session.</param>
public static void BeginSession(JET_INSTANCE instance, out JET_SESID sesid)
{
Api.JetBeginSession(instance, out sesid, null, null);
}
