working on update & delete

This commit is contained in:
Rebecca Schofield 2015-10-05 15:23:49 -05:00
parent c7c701a169
commit 909df70f2d
2 changed files with 29 additions and 18 deletions

View file

@ -214,15 +214,15 @@ Relation DBEngine::setDiff(Relation r1, Relation r2){
//currently all returned relations are called TEMP
Relation new_r = r1;
new_r.setTableName("TEMP");
vector<string> temp;
//bool duplicate = false;
vector<string> temp;
//bool duplicate = false;
int size = 0;
for(int x = 0; x < r2.getAttributes().size(); ++x)
{
for (int i = 0; i < r2.getAttributes()[x].getSize(); ++i)
{
{
temp = r2.getTuple(i);
for(int y = 0; y < new_r.getAttributes().size(); ++y)
@ -244,8 +244,8 @@ Relation DBEngine::setDiff(Relation r1, Relation r2){
size = new_r.getAttributes()[y].getSize();
}
}
}
}
}
}
return new_r;
}
}
@ -283,17 +283,28 @@ Relation DBEngine::crossProduct(Relation r1, Relation r2){
}
return new_r;
return new_r;
}
//UPDATE Senator
//SET Party = Independent
//WHERE Name = Joseph Lieberman
Relation DBEngine::update(Relation r, string attNameSet, string attSet, string attNameWhere, string attWhere){
Relation temp = equality(attNameWhere, attWhere, r);
Relation DBEngine::updateCmd(Relation r, string attNameSet, string attSet, string attNameWhere, string attWhere){
Relation temp = selection(attNameWhere, attWhere, r);
vector<Attribute> atts = temp.getAttributes();
for (int i = 0; i < atts.size(); ++i){
if (atts[i].getName() == attNameSet) {
for (int j = 0; j < atts[i].getSize(); ++j){
atts[i]setValue(attSet, j);
}
break;
}
}
return r;
}
//currently returns a relation with just the changed values, need to look at proper join
//if proper join does not work, plan B is brute force
return temp;
}

View file

@ -21,16 +21,16 @@ public:
Relation& getTableFromName(string n);
void saveToFile(vector<string> cmds);
Relation selection(string attName, string s, Relation r);
Relation projection(vector<string> input, Relation r);
Relation projection(vector<string> input, Relation r);
Relation product(string s1, Relation r1, Relation r2);
void deleteRelation(string n);
void deleteRelation(string n);
void save();
void save(string n);
void storeCommands(string s);
Relation rename(vector<string> newnames, Relation &r);
Relation setUnion(Relation r1, Relation r2);
Relation setDiff(Relation r1, Relation r2);
Relation setDiff(Relation r1, Relation r2);
Relation crossProduct(Relation r1, Relation r2);
Relation update(Relation r, string attNameSet, string attSet, string attNameWhere, string attWhere);
//Relation deleteCmd();
Relation updateCmd(Relation r, string attNameSet, string attSet, string attNameWhere, string attWhere);
//Relation deleteCmd();
};