public static void Read(byte[] byteArray, AllocationUnit allocationUnit)
{
using (var stream = new MemoryStream(byteArray))
{
using (var reader = new BinaryReader(stream))
{
var statusBits = reader.ReadUInt16();
var fixedLengthColumnsLength = reader.ReadUInt16();
// read the fixed column data - since we want to process this data as a stream,
// it is important that we read the data as one big block to advance the stream.
// once it has been read into the block, it can be carved into pieces.
var fixedLengthColumns = reader.ReadBytes(fixedLengthColumnsLength - 4);
var numColumnsInDataRow = reader.ReadUInt16();
var numColumnBitmapLength = (numColumnsInDataRow / 8) + (numColumnsInDataRow % 8 == 0 ? 0 : 1);
var nullabilityBitmap = reader.ReadBytes(numColumnBitmapLength);
// if there are no variable length columns, we're not going to get from
// the stream past this point.
ushort variableLengthColumnsCount = 0;
ushort[] variableLengthColumnsRowOffset = null;
try
{
variableLengthColumnsCount = reader.ReadUInt16();
variableLengthColumnsRowOffset = ReadUInt16Array(reader, variableLengthColumnsCount);
// the rest of the data in the stream are the variable length data; we assume that
// the very next byte is the offset of the first variableLengthColumn. It allows us
// to baseline using the stream rather than using the raw byte array.
for (int ii = 0; ii < variableLengthColumnsRowOffset.Length; ii++)
{
var offsetX = variableLengthColumnsRowOffset[ii];
var offsetY = ii == variableLengthColumnsRowOffset.Length - 1 ? byteArray.Length : variableLengthColumnsRowOffset[ii + 1];
var targetLength = offsetY - offsetX;
var targetArray = new byte[targetLength];
Array.Copy(byteArray, offsetX, targetArray, 0, targetLength);
}
}
catch (EndOfStreamException)
{
}
Console.WriteLine("StatusBits: {0}", statusBits);
Console.WriteLine("FixedLengthColumnsLength: {0}", fixedLengthColumnsLength);
Console.WriteLine("NumColumnsInDataRow: {0}", numColumnsInDataRow);
Console.WriteLine("NumColumnBitmapLength: {0}", numColumnBitmapLength);
Console.WriteLine("NumVariableLengthColumns: {0}", variableLengthColumnsCount);
Console.WriteLine("VariableLengthColumnsRowOffset: {0}", variableLengthColumnsRowOffset);
}
}
}
private Dictionary <long, AllocationUnit> GetAllocationUnits(bool isCacheable = false)
{
if (isCacheable)
{
return(_dataCache.GetItem(
string.Format("{0}.{1}.allocations", _databaseDefinition.DatabaseHost, _databaseDefinition.DatabaseName),
() => GetAllocationUnits(false)));
}
var query = (
"select alloc.allocation_unit_id, schemas.name as [schema], objects.name, objects.object_id " +
" from sys.allocation_units as alloc " +
" join sys.partitions as parts on alloc.container_id = parts.partition_id and alloc.type in (1,3)" +
" join sys.objects as objects on objects.object_id = parts.object_id" +
" join sys.schemas as schemas on schemas.schema_id = objects.schema_id" +
" where objects.type = 'U' " +
" order by [schema], [name] asc;"
);
var allocationsTable = new Dictionary <long, AllocationUnit>();
using (var connection = CreateConnection())
{
var command = connection.CreateCommand();
command.CommandType = CommandType.Text;
command.CommandText = query;
using (var reader = command.ExecuteReader())
{
while (reader.Read())
{
var allocationUnit = new AllocationUnit()
{
AllocationUnitId = Convert.ToInt64(reader.GetValue(0)),
Schema = reader.GetString(1),
TableName = reader.GetString(2),
ObjectId = Convert.ToInt64(reader.GetInt32(3))
};
allocationsTable[allocationUnit.AllocationUnitId] = allocationUnit;
}
}
}
return(allocationsTable);
}
