public IEnumerable <Sqlite3Row> EnumerateRows()
{
IEnumerable <BTreeCellData> cells = BTreeTools.WalkTableBTree(RootPage);
List <ColumnDataMeta> metaInfos = new List <ColumnDataMeta>();
foreach (BTreeCellData cell in cells)
{
metaInfos.Clear();
// Create a new stream to cover any fragmentation that might occur
// The stream is started in the current cells "resident" data, and will overflow to any other pages as needed
using (SqliteDataStream dataStream = new SqliteDataStream(_reader, cell.Page, (ushort)(cell.CellOffset + cell.Cell.CellHeaderSize),
cell.Cell.DataSizeInCell, cell.Cell.FirstOverflowPage, cell.Cell.DataSize))
{
ReaderBase reader = new ReaderBase(dataStream, _reader);
long headerSize = reader.ReadVarInt(out _);
while (reader.Position < headerSize)
{
long columnInfo = reader.ReadVarInt(out _);
ColumnDataMeta meta = new ColumnDataMeta();
if (columnInfo == 0)
{
meta.Type = SqliteDataType.Null;
}
else if (columnInfo == 1)
{
meta.Type = SqliteDataType.Integer;
meta.Length = 1;
}
else if (columnInfo == 2)
{
meta.Type = SqliteDataType.Integer;
meta.Length = 2;
}
else if (columnInfo == 3)
{
meta.Type = SqliteDataType.Integer;
meta.Length = 3;
}
else if (columnInfo == 4)
{
meta.Type = SqliteDataType.Integer;
meta.Length = 4;
}
else if (columnInfo == 5)
{
meta.Type = SqliteDataType.Integer;
meta.Length = 6;
}
else if (columnInfo == 6)
{
meta.Type = SqliteDataType.Integer;
meta.Length = 8;
}
else if (columnInfo == 7)
{
meta.Type = SqliteDataType.Float;
meta.Length = 8;
}
else if (columnInfo == 8)
{
meta.Type = SqliteDataType.Boolean0;
}
else if (columnInfo == 9)
{
meta.Type = SqliteDataType.Boolean1;
}
else if (columnInfo == 10 || columnInfo == 11)
{
throw new ArgumentOutOfRangeException();
}
else if ((columnInfo & 0x01) == 0x00)
{
// Even number
meta.Type = SqliteDataType.Blob;
meta.Length = (uint)((columnInfo - 12) / 2);
}
else
{
// Odd number
meta.Type = SqliteDataType.Text;
meta.Length = (uint)((columnInfo - 13) / 2);
}
metaInfos.Add(meta);
}
object[] rowData = new object[metaInfos.Count];
for (int i = 0; i < metaInfos.Count; i++)
{
ColumnDataMeta meta = metaInfos[i];
switch (meta.Type)
{
case SqliteDataType.Null:
rowData[i] = null;
break;
case SqliteDataType.Integer:
// TODO: Do we handle negatives correctly?
rowData[i] = reader.ReadInteger((byte)meta.Length);
break;
case SqliteDataType.Float:
rowData[i] = BitConverter.Int64BitsToDouble(reader.ReadInteger((byte)meta.Length));
break;
case SqliteDataType.Boolean0:
rowData[i] = false;
break;
case SqliteDataType.Boolean1:
rowData[i] = true;
break;
case SqliteDataType.Blob:
rowData[i] = reader.Read((int)meta.Length);
break;
case SqliteDataType.Text:
rowData[i] = reader.ReadString(meta.Length);
break;
default:
throw new ArgumentOutOfRangeException();
}
}
yield return(new Sqlite3Row(this, cell.Cell.RowId, rowData));
}
}
}
