public string GetString(long rowID, ReadContext readContext)
{
var symRowID = _data.ReadInt32(rowID * INT32_SIZE);
if (symRowID == MetadataConstants.NULL_SYMBOL_VALUE)
{
return(null);
}
#if DEBUG
if (symRowID < 0)
{
throw new IndexOutOfRangeException(_data.Filename + "|" + PropertyName + "|" + rowID + "\n" +
((CompositeRawFile)_data).GetAllUnsafePointers()
+ "\n" + ((CompositeRawFile)_data).GetAllBufferPointers());
}
#endif
var symbolCache = readContext.GetCache(_partitionID, _columnId, _capacity);
string value;
if (symbolCache.IsValueCached(symRowID, out value))
{
return(value);
}
value = _globalSymColumn.GetString(symRowID, readContext);
symbolCache.SetRowID(value, symRowID);
return(value);
}
public IndexAddressColumn(IRawFile kData, int capacity, long recordCountHint)
{
_fileID = kData.FileID;
_partitionID = kData.PartitionID;
int keycountHint = Math.Max(capacity, 1);
// Nuber of records per keyblock
// is a half of statistically expected
// but minimum size is 10
_rowBlockLenBitHint = (int)Math.Floor(Math.Log(Math.Max(recordCountHint / keycountHint / 2, 16), 2.0)) - 1;
_rowBlockLenBitHint = Math.Max(_rowBlockLenBitHint, 4);
int rowBlockLen = 1 << _rowBlockLenBitHint;
_kData = kData;
if (kData.GetAppendOffset() > 0)
{
rowBlockLen = _kData.ReadInt32(ROW_BLOK_LEN_ADDRESS_OFFSET);
_rowBlockLenBitHint = (int)Math.Log(rowBlockLen, 2);
if (1 << _rowBlockLenBitHint != rowBlockLen)
{
throw new NFSdbInvalidStateException("Row block length specified in file '{0}' equals " +
"{1}. Only power of 2 values are supported.",
_kData.Filename, rowBlockLen);
}
}
else if (kData.Access == EFileAccess.ReadWrite)
{
kData.WriteInt64(0, rowBlockLen); // 8
kData.WriteInt64(KEY_BLOCK_ADDRESS_OFFSET, INITIAL_KEYBLOCK_OFFSET); // 8
const int defaultKeyBlockSize = 0;
kData.WriteInt64(INITIAL_KEYBLOCK_OFFSET, defaultKeyBlockSize); // 8
kData.WriteInt64(INITIAL_KEYBLOCK_OFFSET + 8, 0); // 8
kData.SetAppendOffset(INITIAL_APPEND_OFFSET);
}
_rowBlockSize = rowBlockLen * 8 + 8;
}
public int GetInt32(long rowID)
{
return(_storage.ReadInt32(rowID * _sizeBytes));
}
private void Read(IRawFile item, int chunkCount, int chunkSize)
{
Enumerable.Range(0, chunkCount).Select(i => item.ReadInt32(i * chunkSize)).ToArray();
}