//---------------------------------------------------------------------------
// @function:
// CBitSetTest::EresUnittest_Basics
//
// @doc:
// Testing ctors/dtor
//
//---------------------------------------------------------------------------
GPOS_RESULT
CBitSetTest::EresUnittest_Basics()
{
// create memory pool
CAutoMemoryPool amp;
IMemoryPool *pmp = amp.Pmp();
ULONG cSizeBits = 32;
CBitSet *pbs = GPOS_NEW(pmp) CBitSet(pmp, cSizeBits);
ULONG cInserts = 10;
for (ULONG i = 0; i < cInserts; i += 2)
{
// forces addition of new link
pbs->FExchangeSet(i * cSizeBits);
}
GPOS_ASSERT(cInserts / 2 == pbs->CElements());
for (ULONG i = 1; i < cInserts; i += 2)
{
// new link between existing links
pbs->FExchangeSet(i * cSizeBits);
}
GPOS_ASSERT(cInserts == pbs->CElements());
CBitSet *pbsCopy = GPOS_NEW(pmp) CBitSet(pmp, *pbs);
GPOS_ASSERT(pbsCopy->FEqual(pbs));
// delete old bitset to make sure we're not accidentally
// using any of its memory
pbs->Release();
for (ULONG i = 0; i < cInserts; i++)
{
GPOS_ASSERT(pbsCopy->FBit(i * cSizeBits));
}
CWStringDynamic str(pmp);
COstreamString os(&str);
os << *pbsCopy << std::endl;
GPOS_TRACE(str.Wsz());
pbsCopy->Release();
return GPOS_OK;
}
//---------------------------------------------------------------------------
// @function:
// CBitSetTest::EresUnittest_SetOps
//
// @doc:
// Test for set operations
//
//---------------------------------------------------------------------------
GPOS_RESULT
CBitSetTest::EresUnittest_SetOps()
{
// create memory pool
CAutoMemoryPool amp;
IMemoryPool *pmp = amp.Pmp();
ULONG cSizeBits = 32;
ULONG cInserts = 10;
CBitSet *pbs1 = GPOS_NEW(pmp) CBitSet(pmp, cSizeBits);
for (ULONG i = 0; i < cInserts; i += 2)
{
pbs1->FExchangeSet(i * cSizeBits);
}
CBitSet *pbs2 = GPOS_NEW(pmp) CBitSet(pmp, cSizeBits);
for (ULONG i = 1; i < cInserts; i += 2)
{
pbs2->FExchangeSet(i * cSizeBits);
}
CBitSet *pbs = GPOS_NEW(pmp) CBitSet(pmp, cSizeBits);
pbs->Union(pbs1);
GPOS_ASSERT(pbs->FEqual(pbs1));
pbs->Intersection(pbs1);
GPOS_ASSERT(pbs->FEqual(pbs1));
GPOS_ASSERT(pbs->FEqual(pbs));
GPOS_ASSERT(pbs1->FEqual(pbs1));
pbs->Union(pbs2);
GPOS_ASSERT(!pbs->FEqual(pbs1) && !pbs->FEqual(pbs2));
GPOS_ASSERT(pbs->FSubset(pbs1) && pbs->FSubset(pbs2));
pbs->Difference(pbs2);
GPOS_ASSERT(pbs->FEqual(pbs1));
pbs1->Release();
pbs->Union(pbs2);
pbs->Intersection(pbs2);
GPOS_ASSERT(pbs->FEqual(pbs2));
GPOS_ASSERT(pbs->FSubset(pbs2));
GPOS_ASSERT(pbs->CElements() == pbs2->CElements());
pbs2->Release();
pbs->Release();
return GPOS_OK;
}
//---------------------------------------------------------------------------
// @function:
// CBitSetTest::EresUnittest_Removal
//
// @doc:
// Cleanup test
//
//---------------------------------------------------------------------------
GPOS_RESULT
CBitSetTest::EresUnittest_Removal()
{
// create memory pool
CAutoMemoryPool amp;
IMemoryPool *pmp = amp.Pmp();
ULONG cSizeBits = 32;
CBitSet *pbs = GPOS_NEW(pmp) CBitSet(pmp, cSizeBits);
CBitSet *pbsEmpty = GPOS_NEW(pmp) CBitSet(pmp, cSizeBits);
GPOS_ASSERT(pbs->FEqual(pbsEmpty));
GPOS_ASSERT(pbsEmpty->FEqual(pbs));
ULONG cInserts = 10;
for (ULONG i = 0; i < cInserts; i++)
{
pbs->FExchangeSet(i * cSizeBits);
GPOS_ASSERT(i + 1 == pbs->CElements());
}
for (ULONG i = 0; i < cInserts; i++)
{
// cleans up empty links
pbs->FExchangeClear(i * cSizeBits);
GPOS_ASSERT(cInserts - i - 1 == pbs->CElements());
}
GPOS_ASSERT(pbs->FEqual(pbsEmpty));
GPOS_ASSERT(pbsEmpty->FEqual(pbs));
pbs->Release();
pbsEmpty->Release();
return GPOS_OK;
}
//---------------------------------------------------------------------------
// @function:
// CJoinOrderDP::PexprBuildPred
//
// @doc:
// Build predicate connecting the two given sets
//
//---------------------------------------------------------------------------
CExpression *
CJoinOrderDP::PexprBuildPred
(
CBitSet *pbsFst,
CBitSet *pbsSnd
)
{
// collect edges connecting the given sets
CBitSet *pbsEdges = GPOS_NEW(m_pmp) CBitSet(m_pmp);
CBitSet *pbs = GPOS_NEW(m_pmp) CBitSet(m_pmp, *pbsFst);
pbs->Union(pbsSnd);
for (ULONG ul = 0; ul < m_ulEdges; ul++)
{
SEdge *pedge = m_rgpedge[ul];
if (
pbs->FSubset(pedge->m_pbs) &&
!pbsFst->FDisjoint(pedge->m_pbs) &&
!pbsSnd->FDisjoint(pedge->m_pbs)
)
{
#ifdef GPOS_DEBUG
BOOL fSet =
#endif // GPOS_DEBUG
pbsEdges->FExchangeSet(ul);
GPOS_ASSERT(!fSet);
}
}
pbs->Release();
CExpression *pexprPred = NULL;
if (0 < pbsEdges->CElements())
{
DrgPexpr *pdrgpexpr = GPOS_NEW(m_pmp) DrgPexpr(m_pmp);
CBitSetIter bsi(*pbsEdges);
while (bsi.FAdvance())
{
ULONG ul = bsi.UlBit();
SEdge *pedge = m_rgpedge[ul];
pedge->m_pexpr->AddRef();
pdrgpexpr->Append(pedge->m_pexpr);
}
pexprPred = CPredicateUtils::PexprConjunction(m_pmp, pdrgpexpr);
}
pbsEdges->Release();
return pexprPred;
}
//---------------------------------------------------------------------------
// @function:
// CJoinOrderDP::DConnectedness
//
// @doc:
// Return connectedness measure of given component
//
//---------------------------------------------------------------------------
CDouble
CJoinOrderDP::DConnectedness
(
ULONG ulComp
)
{
CBitSet *pbsConnected = GPOS_NEW(m_pmp) CBitSet(m_pmp);
for (ULONG ul = 0; ul < m_ulEdges; ul++)
{
SEdge *pedge = m_rgpedge[ul];
if (pedge->m_pbs->FBit(ulComp))
{
pbsConnected->Union(pedge->m_pbs);
}
}
(void) pbsConnected->FExchangeClear(ulComp);
DOUBLE dConnectedness = (DOUBLE) pbsConnected->CElements() / m_ulComps;
pbsConnected->Release();
return CDouble(dConnectedness);
}
//---------------------------------------------------------------------------
// @function:
// CJoinOrderDP::PexprBestJoinOrder
//
// @doc:
// find best join order for a given set of elements;
//
//---------------------------------------------------------------------------
CExpression *
CJoinOrderDP::PexprBestJoinOrder
(
CBitSet *pbs
)
{
GPOS_CHECK_STACK_SIZE;
GPOS_CHECK_ABORT;
GPOS_ASSERT(NULL != pbs);
// start by looking-up cost in the DP map
CExpression *pexpr = PexprLookup(pbs);
if (pexpr == m_pexprDummy)
{
// no join order could be created
return NULL;
}
if (NULL != pexpr)
{
// join order is found by looking up map
return pexpr;
}
// find maximal covered subset
CBitSet *pbsCovered = PbsCovered(pbs);
if (0 == pbsCovered->CElements())
{
// set is not covered, return a cross product
pbsCovered->Release();
return PexprCross(pbs);
}
if (!pbsCovered->FEqual(pbs))
{
// create a cross product for uncovered subset
CBitSet *pbsUncovered = GPOS_NEW(m_pmp) CBitSet(m_pmp, *pbs);
pbsUncovered->Difference(pbsCovered);
CExpression *pexprResult =
PexprJoinCoveredSubsetWithUncoveredSubset(pbs, pbsCovered, pbsUncovered);
pbsCovered->Release();
pbsUncovered->Release();
return pexprResult;
}
pbsCovered->Release();
// if set has size 2, there is only one possible solution
if (2 == pbs->CElements())
{
return PexprJoin(pbs);
}
// otherwise, compute best join order using dynamic programming
CExpression *pexprBestJoinOrder = PexprBestJoinOrderDP(pbs);
if (pexprBestJoinOrder == m_pexprDummy)
{
// no join order could be created
return NULL;
}
return pexprBestJoinOrder;
}
