void SetUpdater::parse_update() {
while (tokens_.size() > 0 && tokens_.size() % 3 == 0) {
Token attribute = stream_get();
Token op = stream_get();
Token value = stream_get();
if (attribute.first != attribute_name)
throw QuerySyntaxError("Expected attribute name: " + attribute.second);
if (op.first != conditional_eq)
throw QuerySyntaxError("Expected equals operator: " + op.second);
if (value.first > 15 || value.first > 15)
throw QuerySyntaxError("Expected literal value: " + value.second);
record_->set(attribute.second, value.second);
}
if (tokens_.size() != 0)
throw QuerySyntaxError("Set clause syntax error.");
}
bool WhereMatcher::parse_conditional() {
Token left_token = stream_get();
// handling of parenthesis
if (left_token.first == parenthesis_left) {
bool result = parse_and();
Token close_parenthesis = stream_get();
if (close_parenthesis.first != parenthesis_right) {
throw QuerySyntaxError("Invalid syntax, missing closing parenthesis.");
} else {
return result;
}
}
Token op_token = stream_get();
TokenType value_type = left_token.first;
// the left side is an attribute_name, we need to look ahead for the type
if (value_type == attribute_name) {
Token right_token = stream_get();
value_type = right_token.first;
stream_unget(right_token);
}
stream_unget(left_token);
// In C++ you can't declare variables of the same name, even if they were
// never actually declared, this is a really ugly fix, but if there is a way
// to emulate some sort of dynamic typing C++, we could make this a lot better
switch (op_token.first) {
case conditional_eq:
switch (value_type) {
case value_numeral:
return parse_value<float>() == parse_value<float>();
case value_varchar:
case value_date:
case value_time:
return parse_value<string>().compare(parse_value<string>()) == 0;
}
case conditional_neq:
switch (value_type) {
case value_numeral:
return parse_value<float>() != parse_value<float>();
case value_varchar:
case value_date:
case value_time:
return parse_value<string>().compare(parse_value<string>()) != 0;
}
case conditional_lt:
switch (value_type) {
case value_numeral:
return parse_value<float>() < parse_value<float>();
case value_varchar:
case value_date:
case value_time:
return parse_value<string>().compare(parse_value<string>()) > 0;
}
case conditional_gt:
switch (value_type) {
case value_numeral:
return parse_value<float>() > parse_value<float>();
case value_varchar:
case value_date:
case value_time:
return parse_value<string>().compare(parse_value<string>()) < 0;
}
break;
case conditional_lte:
switch (value_type) {
case value_numeral:
return parse_value<float>() <= parse_value<float>();
case value_varchar:
case value_date:
case value_time:
return parse_value<string>().compare(parse_value<string>()) >= 0;
}
break;
case conditional_gte:
switch (value_type) {
case value_numeral:
return parse_value<float>() >= parse_value<float>();
case value_varchar:
case value_date:
case value_time:
return parse_value<string>().compare(parse_value<string>()) <= 0;
}
break;
default:
throw QuerySyntaxError("Unrecognized symbol: " + left_token.second);
}
throw QuerySyntaxError("Unknown type, internal error");
}
