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write to file #2

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123 changes: 98 additions & 25 deletions project4/mydatabase.c
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Original file line number Diff line number Diff line change
Expand Up @@ -56,7 +56,6 @@ int matchSpecs(Tuple ct, Tuple lt) {
}
return 1;
}

}

int hash(char* key) {
Expand All @@ -65,7 +64,7 @@ int hash(char* key) {
for (int i = 0; key[i] != '\0'; i++) {
sum += key[i];
}

return sum % NBUCKETS;
}

Expand Down Expand Up @@ -101,32 +100,46 @@ void insert(Tuple t, Hashtable h) {
printf("inserting...\n");
bucketInsert(t, &(h[hash(t.key)]));
}

}

int cmpTuple(Tuple a, Tuple b) {
/*int cmpTuple(Tuple a, Tuple b) {
if(a.nAttr == b.nAttr && a.key == b.key) {
for(int i=0; i< a.nAttr; i++) {
//returns false if any of the attributes do not match
if(a.attr[i] != b.attr[i]) {
return 0;
}
}
//if the above condition is
//if the above condition is
//never satisfied in the for loop, we return 1
return 1;
} else {
printf("Number of attributes or keys don't match\n");
}

return 0;

}
}*/

void printTuple(Tuple t){
printf("tuple(%s, %d, %s, %s, %s)\n",t.key, t.nAttr, t.attr[0], t.attr[1], t.attr[2]);
}

/*
void filePrintTuple(Tuple t, char *filename){
FILE *fp;
fp = fopen(filename, "a");
fseek(fp, 0, SEEK_END); // goto end of file
{
if (fp == NULL) {
perror("Can't open file");
} else if (ftell(fp) == 0)
{
fprintf(fp, "tuple(%s, %d, %s, %s, %s)\n",t.key, t.nAttr, t.attr[0], t.attr[1], t.attr[2]);}
fclose(fp);
}}*/

void printTable(Hashtable h) {
for(int i=0; i<NBUCKETS; i++) {
Tuple *curr = h[i];
Expand All @@ -137,6 +150,23 @@ void printTable(Hashtable h) {
}
}

//fixed
void filePrintTable(Hashtable h, char *filename) {
FILE *fp;
fp = fopen(filename, "a");
fseek(fp, 0, SEEK_END); // go to end of file
if (ftell(fp) == 0){//if file is empty
for(int i=0; i<NBUCKETS; i++) {
Tuple *curr = h[i];
while(curr != NULL) {
//filePrintTuple(*curr, filename);
{
if (fp == NULL) {
perror("Can't open file");
} else
{
fprintf(fp, "tuple(%s, %d, %s, %s, %s)\n", curr->key, curr->nAttr, curr->attr[0], curr->attr[1], curr->attr[2]);}



void bucketDelete(Tuple t, List *head) {
Expand All @@ -145,7 +175,7 @@ void bucketDelete(Tuple t, List *head) {
} else {
Tuple *curr = *head;
Tuple *trail = NULL;

while(curr != NULL) {
if(matchSpecs(t, *curr)) {
break;
Expand All @@ -161,56 +191,99 @@ void bucketDelete(Tuple t, List *head) {
//case 3 delete from head node
if(*head == curr) {
*head = (*head)->next;

} else {//case 4 delete beyond head
trail->next = curr->next;

}
free(curr);
}

}
}


void delete(Tuple t, Hashtable h ) {
void bucketLookup(Tuple t, List *head) {
if(*head == NULL) {
printf("Cannot lookup from empty list\n");
} else {
Tuple *curr = *head;
Tuple *trail = NULL;

while(curr != NULL) {
if(matchSpecs(t, *curr)) {
printTuple(t);
break;
} else {
trail = curr;
curr = curr->next;
}
}
//case 2 not found tuple
if(curr == NULL) {
printf("tuple was not found\n");
}
free(curr);
}

}


void tupleDelete(Tuple t, Hashtable h ) {
printf("deleting...\n");
bucketDelete(t, &h[hash(t.key)]);
}

void lookup(Tuple t, Hashtable h){
printf("finding tuple...\n");
bucketLookup(t, &h[hash(t.key)]);
}


int main(void) {
Hashtable csg;

for(int i = 0; i< NBUCKETS; i++) {

csg[i] = NULL;
}


Tuple c = tuple_new("John Lennon", 3, "CSC282", "John Lennon", "A-");
insert(c, csg);



Tuple a = tuple_new("Luke Skywalker", 3,"CSC173", "Luke Skywalker", "A");
insert(a, csg);

Tuple b = tuple_new("Luke Skywalker", 3,"MTH201", "Luke Skywalker", "C-");
insert(b, csg);

/*Tuple x = tuple_new("Luke Skywalker", 3,"*", "*", "*");
insert(x, csg);*/

/*Tuple b = tuple_new("Luke Skywalker", 3,"MTH201", "Luke Skywalker", "C-");
insert(b, csg);*/

Tuple d = tuple_new("George Eastman", 3, "MUR110", "George Eastman", "A+");
insert(d, csg);

Tuple e = tuple_new("George Eastman", 3, "*", "*", "*");


Tuple e = tuple_new("George East", 3, "*", "*", "*");
insert(e,csg);

Tuple f = tuple_new("George Eastman", 3, "*", "*", "*");

//printf("a ?= d %d", matchSpecs(e,a));
printTable(csg);
delete(e,csg);
printTable(csg);
//lookup(f,csg);
//tupleDelete(e,csg);
//lookup(e,csg);
//lookup(f,csg);
filePrintTable(csg,"Test0.txt");
tupleDelete(f,csg);
//lookup(d,csg);
//lookup(f,csg);
//lookup(e,csg);
//printTable(csg);

filePrintTable(csg,"Test.txt");//working now


return 0;
}