DBMS Requirements: RangeJoinTable

Class RangeJoinTable {

bool connect(const char* aUserName, const char* aPassword);

bool disconnect();

bool openTable(const char* aTableName1, const char* aTableName2);

void setComparisionOp (CompOp aOp);

void* fetch();

bool closeTable();

}

enum CompOp {

GT, //greater than

LT, //less than

LE, //less than or equal to

GE, //greater than or equal to

}

RangeJoinTable Guidelines

Assume both table has only two fields, both of type integer.
Use DBAPI classes to implement the above methods.
fetch() method should retrieve record using table1->fetch(), get record from table2->fetch() for matching f1 value (based on CompOp set) in table1.
After fetch is called on both the tables, populate buffer to hold values of t1.f1, t1.f2, t2.f2 and return pointer to this buffer.

RangeJoinTable Guidelines

int main() {

RangeJoinTable sTable;

sTable.connect("root", "manager");

sTable.openTable("T1", "T2");

sTable.setComparisonOp(LE);

char* record;

while (true) {

record = (char*) sTable.fetch();

if (record == NULL) break;

printf("Tuple t1.f1=%d t1.f2=%d t2.f2=%d n",

*(int*) record,

*(int*) (record + sizeof(int)),

*(int*) (record + sizeof(int) * 2));

}

sTable.closeTable();

sTable.disconnect();

return 0;

}

Assumption: Table T1, T2 with field f1 and f2, both of type integer already exists in database

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