public WAHBitArray Query(RDBExpression ex, object from, int maxsize)
{
// always return everything
return(WAHBitArray.Fill(maxsize));
}
private WAHBitArray ExecutionPlan(string filter, int maxsize)
{
//_log.Debug("query : " + filter);
DateTime dt = FastDateTime.Now;
// query indexes
string[] words = filter.Split(' ');
//bool defaulttoand = true;
//if (filter.IndexOfAny(new char[] { '+', '-' }, 0) > 0)
// defaulttoand = false;
WAHBitArray found = null;// WAHBitArray.Fill(maxsize);
foreach (string s in words)
{
int c;
bool not = false;
string word = s;
if (s == "")
{
continue;
}
OPERATION op = OPERATION.AND;
//if (defaulttoand)
// op = OPERATION.AND;
if (word.StartsWith("+"))
{
op = OPERATION.OR;
word = s.Replace("+", "");
}
if (word.StartsWith("-"))
{
op = OPERATION.ANDNOT;
word = s.Replace("-", "");
not = true;
if (found == null) // leading with - -> "-oak hill"
{
found = WAHBitArray.Fill(maxsize);
}
}
if (word.Contains("*") || word.Contains("?"))
{
WAHBitArray wildbits = new WAHBitArray();
// do wildcard search
Regex reg = new Regex("^" + word.Replace("*", ".*").Replace("?", ".") + "$", RegexOptions.IgnoreCase);
foreach (string key in _words.Keys())
{
if (reg.IsMatch(key))
{
_words.TryGetValue(key, out c);
WAHBitArray ba = _bitmaps.GetBitmap(c);
wildbits = DoBitOperation(wildbits, ba, OPERATION.OR, maxsize);
}
}
if (found == null)
{
found = wildbits;
}
else
{
if (not) // "-oak -*l"
{
found = found.AndNot(wildbits);
}
else if (op == OPERATION.AND)
{
found = found.And(wildbits);
}
else
{
found = found.Or(wildbits);
}
}
}
else if (_words.TryGetValue(word.ToLowerInvariant(), out c))
{
// bits logic
WAHBitArray ba = _bitmaps.GetBitmap(c);
found = DoBitOperation(found, ba, op, maxsize);
}
else if (op == OPERATION.AND)
{
found = new WAHBitArray();
}
}
if (found == null)
{
return(new WAHBitArray());
}
// remove deleted docs
WAHBitArray ret;
if (_docMode)
{
ret = found.AndNot(_deleted.GetBits());
}
else
{
ret = found;
}
//_log.Debug("query time (ms) = " + FastDateTime.Now.Subtract(dt).TotalMilliseconds);
return(ret);
}