c4_JoinViewer::c4_JoinViewer(c4_Sequence &seq_, const c4_View &keys_, const
c4_View &view_, bool outer_): _parent(&seq_), _argView(view_.SortOn(keys_)) {
// why not in GetTemplate, since we don't need to know this...
_template = _parent.Clone();
for (int l = 0; l < _argView.NumProperties(); ++l)
_template.AddProperty(_argView.NthProperty(l));
c4_View sorted = _parent.SortOn(keys_).Project(keys_);
c4_View temp = _argView.Project(keys_);
_base.SetSize(0, 5);
_offset.SetSize(0, 5);
int j = 0, n = 0;
for (int i = 0; i < sorted.GetSize(); ++i) {
int orig = _parent.GetIndexOf(sorted[i]);
d4_assert(orig >= 0);
if (i > 0 && sorted[i] == sorted[i - 1]) {
// if last key was same, repeat the same join
int last = _offset.GetSize() - n;
for (int k = 0; k < n; ++k) {
_base.Add(orig);
_offset.Add(_offset.GetAt(last + k));
}
} else
{ // no, this is a new combination
bool match = false;
// advance until the temp view entry is >= this sorted entry
while (j < temp.GetSize())
if (sorted[i] <= temp[j]) {
match = sorted[i] == temp[j];
break;
} else
++j;
n = 0;
if (match) {
do {
_base.Add(orig);
_offset.Add(j);
++n;
} while (++j < temp.GetSize() && temp[j] == temp[j - 1]);
} else if (outer_) {
// no match, add an entry anyway if this is an outer join
_base.Add(orig);
_offset.Add(~(t4_i32)0); // special null entry
++n;
}
}
}
}
v1.Add(p1[345] + p2["four"]); v1.Add(p1[234] + p2["five"]); v1.Add(p1[123] + p2["six"]); c4_View v2 = v1.Sort(); A(v2.GetSize() == 6); A(p1(v2[0]) == 111); A(p1(v2[1]) == 123); A(p1(v2[2]) == 222); A(p1(v2[3]) == 234); A(p1(v2[4]) == 333); A(p1(v2[5]) == 345); A(v2.Search(p1[123]) == 1); A(v2.Search(p1[100]) == 0); A(v2.Search(p1[200]) == 2); A(v2.Search(p1[400]) == 6); c4_View v3 = v1.SortOn(p2); A(v3.GetSize() == 6); A(p1(v3[0]) == 234); A(p1(v3[1]) == 345); A(p1(v3[2]) == 111); A(p1(v3[3]) == 123); A(p1(v3[4]) == 333); A(p1(v3[5]) == 222); A(v3.Search(p2["six"]) == 3); A(v3.Search(p2["aha"]) == 0); A(v3.Search(p2["gee"]) == 2); A(v3.Search(p2["wow"]) == 6); c4_View v4 = v1.SortOnReverse(p2, p2); A(v4.GetSize() == 6); A(p1(v4[0]) == 222); A(p1(v4[1]) == 333);