74 lines
1.8 KiB
C++
74 lines
1.8 KiB
C++
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#include "DBEngine.h"
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using namespace std;
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DBEngine::DBEngine(){
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//
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}
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//create a new table in memory
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void DBEngine::createCmd(){
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//
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}
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//open a txt file, parse SQL script, load data in table
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//void DBEngine::openCmd(){
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//
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//}
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//should write cmdList to a .txt file
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void DBEngine::saveCmd(){
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//
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}
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//display the database
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void DBEngine::showCmd(){
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//
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}
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//add a tuple to a table in the memory
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void DBEngine::insertQuery(){
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//
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}
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//remove a tuple from a table in the memory
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void DBEngine::deleteQuery(){
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//
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}
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//search and return one more tuples from a table in the memory
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void DBEngine::selectQuery(){
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//
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}
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//return a subset of attributes (columns)
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/*
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vector<string> DBEngine::projectQuery(Relation table, string query){
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/*
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So basically this is what's going on:
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- Take the table to iterate through, this is the relation (input 1)
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- Take a string that will be used for the program to search for in the attributes (input 2)
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- Iterate through each attribute until the attribute (string) matches the input query
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- For every iterator, have a counter that counts how many attributes are skipped over in the vector until the attribute is found
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- This counter will be used to iterate through each vector (row) in the list, skip over that many attributes, and push that into a result vector
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- Once all vector's elements at the specified attribute are pushed back, return the result vector
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for(int i = 0; i < table.getSize(); i++) {
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}
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}
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*/
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//each row in the first table is paired with all the rows in the second table
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void DBEngine::productQuery(){
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//
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}
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//true if relations have the same # of attributes and each attribute must be from the same domain
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bool DBEngine::unionComp(){
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return false;
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}
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