Update DBEngine.cpp
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1 changed files with 20 additions and 4 deletions
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DBEngine.cpp
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DBEngine.cpp
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@ -42,10 +42,26 @@ void DBEngine::selectQuery(){
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}
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//return a subset of attributes (columns)
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void DBEngine::projectQuery(){
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//
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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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