MyItr * Table::index_find(int op, string key_to_btree, Tuple to_find )
{
//cout << op << endl;
map<string, BTree*>::iterator map_itr = keys.find( key_to_btree );
MyItr * itr = NULL;
//tuples.push_back( myItr->first() ); // get the headers
// if there is not index for the column, should never happen
if ( map_itr == keys.end() )
{
return NULL;
}
BTree * btree = map_itr->second;
if ( op == OP_EQUAL )
{
//cout << "euql " << endl;
BTreeNode * node = btree->find( to_find );
if ( node == NULL )
return NULL;
for ( int i = 0; i < node->getCount(); i++ )
{
if ( to_find == ( (LeafNode *) node )->get_values()[i] )
{
vector<streampos> offset = ( (LeafNode *) node )->get_values()[i].offset;
//cout << offset.size() << endl;
itr = index_fetch( offset );
}
}
}
else if ( op == OP_LEQ )
{
BTreeNode * node = btree->find_leq( to_find );
if ( node == NULL )
return NULL;
BTreeNode * cur_node = node;
vector<string> tuples;
myItr->open();
tuples.push_back( myItr->first() );
myItr->close();
itr = new MyItr( name, tuples );
while( node )
{
for ( int i = node->getCount() - 1; i >= 0; i-- )
{
if ( ( (LeafNode *) node )->get_values()[i] <= to_find)
{
vector<streampos> offset = ( (LeafNode *) node )->get_values()[i].offset;
*itr += *( index_fetch( offset ) );
}
}
node = node->getLeftSibling();
}
}
else if ( op == OP_LT )
{
BTreeNode * node = btree->find_leq( to_find );
if ( node == NULL )
return NULL;
BTreeNode * cur_node = node;
vector<string> tuples;
myItr->open();
tuples.push_back( myItr->first() );
myItr->close();
itr = new MyItr( name, tuples );
//cout << " at least here" << endl;
while( node )
{
for ( int i = node->getCount() - 1; i >= 0; i-- )
{
if ( ( (LeafNode *) node )->get_values()[i] < to_find)
{
vector<streampos> offset = ( (LeafNode *) node )->get_values()[i].offset;
*itr += *( index_fetch( offset ) );
}
}
node = node->getLeftSibling();
}
}
else if ( op == OP_GEQ )
{
BTreeNode * node = btree->find_geq( to_find );
if ( node == NULL )
return NULL;
BTreeNode * cur_node = node;
vector<string> tuples;
myItr->open();
tuples.push_back( myItr->first() );
myItr->close();
itr = new MyItr( name, tuples );
//cout << " at least here" << endl;
while( node )
{
for ( int i = 0; i < node->getCount(); i++ )
{
if ( ( (LeafNode *) node )->get_values()[i] >= to_find)
{
vector<streampos> offset = ( (LeafNode *) node )->get_values()[i].offset;
*itr += *( index_fetch( offset ) );
}
}
node = node->getRightSibling();
}
}
else if ( op == OP_GT )
{
//cout << "GT" << endl;
BTreeNode * node = btree->find_geq( to_find );
if ( node == NULL )
return NULL;
BTreeNode * cur_node = node;
vector<string> tuples;
myItr->open();
tuples.push_back( myItr->first() );
myItr->close();
itr = new MyItr( name, tuples );
//cout << " at least here" << endl;
//cout << node << endl;
while( node )
{
for ( int i = 0; i < node->getCount(); i++ )
{
if ( ( (LeafNode *) node )->get_values()[i] > to_find)
{
vector<streampos> offset = ( (LeafNode *) node )->get_values()[i].offset;
*itr += *( index_fetch( offset ) );
}
}
node = node->getRightSibling();
}
}
else
{
cerr << "Error in Table::index_find(): should never be here." << endl;
return NULL;
}
return itr;
}
BTreeNode* InternalNode::remove(int value)
{ // to be written by students
BTreeNode* ptr;
// int pos = Position(value);
int pos;
for(pos = count -1; pos > 0 && keys[pos] > value; pos--);
BTreeNode* random = children[pos]->remove(value);
if(random != NULL)
{
BTreeNode* hey = random;
if (hey->getCount() == internalSize)
return hey;
delete random;
int temp_zero_location;
for (int i = 0; i < count; i++)
{
if (keys[i] == 0)
{
temp_zero_location = i;
}
}
for (int j = temp_zero_location; j < count; j++)
{
keys[j] = keys[j+1];
children[j] = children[j+1];
}
count--;
if(parent)
{
parent->resetMinimum(this);
}
if (count < (internalSize+1)/2)// && parent != NULL)
{
//borrow from left sibling
// ((InternalNode*)leftSibling);
if(((InternalNode*)leftSibling))
{ //If Left sibling is there
if(((InternalNode*)leftSibling)->getCount()-1 < (internalSize+1)/2)
{
for (int i = (count -1); i >= 0; i--)
{
((InternalNode*)leftSibling)->insert(children[i]);
}
((InternalNode*)leftSibling)->setRightSibling(((InternalNode*)rightSibling));
return ((InternalNode*)leftSibling);
}
}
// else{
// }
// ((InternalNode*)rightSibling);
else if(((InternalNode*)rightSibling))
{
if((((InternalNode*)rightSibling)->getCount()-1) < (internalSize+1)/2)
{
for (int i = (count - 1); i >= 0; i--)
{
((InternalNode*)rightSibling)->insert(children[i]);
}
BTreeNode* temp = this->getRightSibling();
temp->setLeftSibling(((InternalNode*)leftSibling));
return temp;
// else{
}
}
}
}
if (count == 1)
{
children[0]->setParent(NULL);
return children[0];
}
return NULL;
}