int condition()
{ Token op;
int changeSpot = 0;
if(token.sym == oddsym)
{
getToken();
expression();
//odd command
emit(2, 0, 6);
}
else
{
expression();
if(!isRelation())
getError(8);
op = token;
getToken();
expression();
changeSpot = writeRelation(op.sym);
}
return changeSpot;
}
bool QueryEvaluator::evaluateSTClause(TNode * ST_node,
vector<int> row,
vector<vector<int>> * new_rows,
ResultTable * temp_result) {
TNode * rlt_node = ST_node->getChildAtIndex(0);
TNode * arg1_node = rlt_node->getChildAtIndex(0);
TNode * arg2_node = rlt_node->getChildAtIndex(1);
Symbol rlt = rlt_node->getType();
Symbol arg1_type = arg1_node->getType();
Symbol arg2_type = arg2_node->getType();
string type1 = table.getType(arg1_node->getValue());
string type2 = table.getType(arg2_node->getValue());
int arg1_index = temp_result->getSymbolIndex(arg1_node->getValue());
int arg2_index = temp_result->getSymbolIndex(arg2_node->getValue());
int arg1_val; int arg2_val;
switch (arg1_type) {
case Underline:
{
switch (arg2_type) {
case Underline:
return true;
case Const:
{
arg2_val = getIndexOfConst(arg2_node, rlt, ARG2);
vector<int> arg1_vals = getArgInRelation(rlt, arg2_val, ARG1);
if (!arg1_vals.empty()) return true;
break;
}
case QuerySymbol:
{
// get stored value of arg2 in row
arg2_val = row[arg2_index];
if (arg2_val!=-1) {
vector<int> arg1_vals = getArgInRelation(rlt, arg2_val, ARG1);
if (!arg1_vals.empty()) {
new_rows->push_back(row);
return true;
}
break;
}
vector<int> arg2_vals = getAllPKBValues(arg2_node->getValue());
for (size_t i=0; i<arg2_vals.size(); i++) {
vector<int> arg1_vals = getArgInRelation(rlt, arg2_vals[i], ARG1);
if (!arg1_vals.empty()) {
row[arg2_index] = arg2_vals[i];
new_rows->push_back(row);
}
}
break;
}
default:
break;
}
break;
}
case Const:
{
arg1_val = getIndexOfConst(arg1_node, rlt, ARG1);
switch (arg2_type) {
case Underline:
{
vector<int> arg2_vals = getArgInRelation(rlt, arg1_val, ARG2);
if (!arg2_vals.empty()) return true;
break;
}
case Const:
{
arg2_val = getIndexOfConst(arg2_node, rlt, ARG2);
return isRelation(rlt, arg1_val, arg2_val);
}
case QuerySymbol:
{
// get value of arg2 in row
arg2_val = row[arg2_index];
if (arg2_val!=-1) {
if (isRelation(rlt, arg1_val, arg2_val)) {
new_rows->push_back(row);
return true;
}
}
vector<int> arg2_vals = getArgInRelation(rlt, arg1_val, ARG2);
arg2_vals = removeInvalidValues(arg2_vals, arg2_node->getValue());
// save new values of arg2 to new_rows
for (size_t i=0; i<arg2_vals.size(); i++) {
row[arg2_index] = arg2_vals[i];
new_rows->push_back(row);
}
break;
}
default:
break;
}
break;
}
case QuerySymbol:
{
arg1_val = row[arg1_index];
switch (arg2_type) {
case Underline:
{
if (arg1_val!=-1) {
vector<int> arg2_vals = getArgInRelation(rlt, arg1_val, ARG2);
if (!arg2_vals.empty()) {
new_rows->push_back(row);
return true;
}
}
vector<int> arg1_vals = getAllPKBValues(arg1_node->getValue());
for (size_t i=0; i<arg1_vals.size(); i++) {
vector<int> arg2_vals = getArgInRelation(rlt, arg1_vals[i], ARG2);
if (!arg2_vals.empty()) {
row[arg1_index] = arg1_vals[i];
new_rows->push_back(row);
}
}
break;
}
case Const:
{
arg2_val = getIndexOfConst(arg2_node, rlt, ARG2);
if (arg1_val!=-1) {
if (isRelation(rlt, arg1_val, arg2_val)) {
new_rows->push_back(row);
return true;
}
}
vector<int> arg1_vals = getArgInRelation(rlt, arg2_val, ARG1);
arg1_vals = removeInvalidValues(arg1_vals, arg1_node->getValue());
//save arg1_vals to new_rows
for (size_t i=0; i<arg1_vals.size(); i++) {
row[arg1_index] = arg1_vals[i];
new_rows->push_back(row);
}
break;
}
case QuerySymbol:
{
// get value of arg2 in row
arg2_val = row[arg2_index];
if (arg1_val!=-1 && arg2_val!=-1) {
if (isRelation(rlt, arg1_val, arg2_val)) {
new_rows->push_back(row); return true;
}
} else if (arg1_val!=-1 && arg2_val==-1) {
vector<int> arg2_vals = getArgInRelation(rlt, arg1_val, ARG2);
arg2_vals = removeInvalidValues(arg2_vals, arg2_node->getValue());
for (size_t i=0; i<arg2_vals.size(); i++) {
row[arg2_index] = arg2_vals[i];
new_rows->push_back(row);
}
} else if (arg1_val==-1 && arg2_val!=-1) {
vector<int> arg1_vals = getArgInRelation(rlt, arg2_val, ARG1);
arg1_vals = removeInvalidValues(arg1_vals, arg1_node->getValue());
for (size_t i=0; i<arg1_vals.size(); i++) {
row[arg1_index] = arg1_vals[i];
new_rows->push_back(row);
}
} else {
vector<int> arg1_vals = getAllPKBValues(arg1_node->getValue());
for (size_t i=0; i<arg1_vals.size(); i++) {
if (arg1_index==arg2_index) {
if (isRelation(rlt, arg1_vals[i], arg1_vals[i])) {
row[arg1_index] = arg1_vals[i];
new_rows->push_back(row);
}
} else {
vector<int> arg2_vals = getArgInRelation(rlt, arg1_vals[i], ARG2);
arg2_vals = removeInvalidValues(arg2_vals, arg2_node->getValue());
for (size_t j=0; j<arg2_vals.size(); j++) {
row[arg1_index] = arg1_vals[i]; row[arg2_index] = arg2_vals[j];
new_rows->push_back(row);
}
}
}
}
break;
}
default:
break;
}
break;
}
default:
break;
}
if (!new_rows->empty()) return true;
return false;
}
