public PrimaryRecord(byte[] bytes, Page page)
: base(page)
{
short offset = 0;
// Parse status bits A
parseStatusBitsA(new BitArray(new [] { bytes[offset++] }));
// TODO: Strategize this stuff to avoid ifs, switches & impersonation
if(Type == RecordType.ForwardingStub)
{
// Forwarding stub only has one status byte. Remaining 8 bytes are for (PageID, FileID, Slot)
FixedLengthData = bytes.Skip(1).Take(8).ToArray();
int pageID = BitConverter.ToInt32(bytes, 1);
short fileID = BitConverter.ToInt16(bytes, 5);
short slot = BitConverter.ToInt16(bytes, 7);
var forwardPage = page.Database.GetPrimaryRecordPage(new PagePointer(fileID, pageID), CompressionContext.NoCompression);
byte[] forwardedRecordBytes = forwardPage.Records[slot].RawBytes;
parseStatusBitsA(new BitArray(new[] {forwardedRecordBytes[0]}));
bytes = forwardedRecordBytes;
// We'll impersonate the ForwardingStub record type that we originated from, this allows
// the engine to distinguish BlobFragments and the records that actually reference them.
Type = RecordType.ForwardingStub;
}
// Parse status bits B
parseStatusBitsB(bytes[offset++]);
// Parse fixed length size
short fixedLengthSize = BitConverter.ToInt16(bytes, offset);
fixedLengthSize -= 4;
offset += 2;
// Parse fixed length data
FixedLengthData = bytes.Skip(offset).Take(fixedLengthSize).ToArray();
offset += fixedLengthSize;
// Parse number of columns
NumberOfColumns = BitConverter.ToInt16(bytes, offset);
offset += 2;
// Parse null bitmap, if present
if (HasNullBitmap)
offset = ParseNullBitmap(bytes, ref offset);
// Parse variable length columns, if present
if (HasVariableLengthColumns)
ParseVariableLengthColumns(bytes, ref offset);
// Save complete record raw bytes
RawBytes = bytes.Take(offset).ToArray();
}
internal CompressedRecord(byte[] record, Page page)
{
this.record = record;
this.page = page;
short recordPointer = 1;
parseHeader();
parseCDRegion(ref recordPointer);
parseShortDataRegion(ref recordPointer);
parseLongDataRegion(ref recordPointer);
}
public BlobInlineRootProxy(Page page, byte[] data)
: base(page)
{
this.data = data;
// Parsed according to table 7-1 (p. 378) in [SQL Server 2008 Internals]
complexColumnType = data[0];
indexLevel = BitConverter.ToInt16(data, 1);
unused = data[3];
sequence = BitConverter.ToInt32(data, 4);
// Technically a 6-byte long value. Low two bytes always zero, thus not stored (http://bit.ly/mdAQpm)
timestamp = BitConverter.ToUInt32(data, 8) << 16;
}
public TextPointerProxy(Page page, byte[] bytes)
: base(page)
{
this.bytes = bytes;
/* 16 byte LOB Textpointer:
*
* Bytes Content
* 0-3 Timestamp (int)
* 4-7 ?
* 8-16 Slot pointer
*/
timestamp = BitConverter.ToInt32(bytes, 0);
lobRootSlot = new SlotPointer(bytes.Skip(8).ToArray());
}
public IndexRecord(byte[] bytes, Page page)
: base(page)
{
parseStatusBitsA(new BitArray(new[] { bytes[0] }));
// Index records don't contain fixed length header - it's stored in the page header
FixedLengthData = bytes.Skip(1).Take(Page.Header.Pminlen - 1).ToArray();
short offset = Page.Header.Pminlen;
NumberOfColumns = BitConverter.ToInt16(bytes, offset);
offset += 2;
if (HasNullBitmap)
offset = ParseNullBitmap(bytes, ref offset);
if (HasVariableLengthColumns)
ParseVariableLengthColumns(bytes, ref offset);
}
public TextRecord(byte[] bytes, Page page)
: base(page)
{
short offset = 0;
// Parse status bits, even though we currently ignore their values.
// Only one I can currently imagine being relevant is HasVersioningInformation.
parseStatusBitsA(new BitArray(new [] { bytes[offset++] }));
parseStatusBitsB(bytes[offset++]);
// Read the fixed length portion
short fixedLengthSize = BitConverter.ToInt16(bytes, offset);
fixedLengthSize -= 4;
offset += 2;
FixedLengthData = bytes.Skip(offset).Take(fixedLengthSize).ToArray();
offset += fixedLengthSize;
// No matter the text structure, they all have a common 14 byte header
parseCommonTextStructureHeader();
// Save complete record raw bytes
RawBytes = bytes.Take(offset).ToArray();
}
protected DataProxy(Page page)
{
OriginPage = page;
}