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/*
* Copyright (c) 2022, Jan de Visser <jan@de-visser.net>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibSQL/ResultSet.h>
namespace SQL {
size_t ResultSet::binary_search(Tuple const& sort_key, size_t low, size_t high)
{
if (high <= low) {
auto compare = sort_key.compare(at(low).sort_key);
return (compare > 0) ? low + 1 : low;
}
auto mid = (low + high) / 2;
auto compare = sort_key.compare(at(mid).sort_key);
if (compare == 0)
return mid + 1;
if (compare > 0)
return binary_search(sort_key, mid + 1, high);
return binary_search(sort_key, low, mid);
}
void ResultSet::insert_row(Tuple const& row, Tuple const& sort_key)
{
if ((sort_key.size() == 0) || is_empty()) {
empend(row, sort_key);
return;
}
auto ix = binary_search(sort_key, 0, size() - 1);
insert(ix, ResultRow { row, sort_key });
}
void ResultSet::limit(size_t offset, size_t limit)
{
if (offset > 0) {
if (offset > size()) {
clear();
return;
}
remove(0, offset);
}
if (size() > limit)
remove(limit, size() - limit);
}
}
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