/// Extract all subfunctions of the main conjunction, but depending only on the specified columns
static void extractFunctions(ASTPtr expression, const NameSet & columns, std::vector<ASTPtr> & result)
{
const ASTFunction * function = typeid_cast<const ASTFunction *>(&*expression);
if (function && function->name == "and")
{
for (size_t i = 0; i < function->arguments->children.size(); ++i)
extractFunctions(function->arguments->children[i], columns, result);
}
else if (isValidFunction(expression, columns))
{
result.push_back(expression->clone());
}
}
/// Verifying that the function depends only on the specified columns
static bool isValidFunction(ASTPtr expression, const NameSet & columns)
{
for (size_t i = 0; i < expression->children.size(); ++i)
if (!isValidFunction(expression->children[i], columns))
return false;
if (const ASTIdentifier * identifier = typeid_cast<const ASTIdentifier *>(&*expression))
{
if (identifier->kind == ASTIdentifier::Kind::Column)
return columns.count(identifier->name);
}
return true;
}
void Aggregate::setFunction(unsigned func_idx, Function *func)
{
//Case the function index is invalid raises an error
if(func_idx!=FINAL_FUNC && func_idx!=TRANSITION_FUNC)
throw Exception(ERR_REF_FUNCTION_INV_TYPE,__PRETTY_FUNCTION__,__FILE__,__LINE__);
//Checks if the function is valid, if not the case raises an error
if(!isValidFunction(func_idx, func))
throw Exception(Exception::getErrorMessage(ERR_USING_INV_FUNC_CONFIG)
.arg(Utf8String::create(this->getName()))
.arg(BaseObject::getTypeName(OBJ_AGGREGATE)),
ERR_USING_INV_FUNC_CONFIG,__PRETTY_FUNCTION__,__FILE__,__LINE__);
functions[func_idx]=func;
}
