HybridNitroSQLiteQueryResult.cpp

#include "HybridNitroSQLiteQueryResult.hpp"
#include <NitroModules/ArrayBuffer.hpp>
#include <NitroModules/Null.hpp>
#include <NitroModules/Promise.hpp>
#include <unordered_map>
#include <variant>
#include <vector>

namespace margelo::nitro::rnnitrosqlite {

namespace {

  /**
   * Compute the approximate external memory size of a single result row.
   * This includes:
   * - Column name string capacities,
   * - Heap usage for the actual SQLiteValue contents.
   */
  size_t getRowExternalMemorySize(const SQLiteQueryResultRow& row) {
    size_t bucketMemory = row.bucket_count() * sizeof(void*);
    constexpr size_t nodePadding = 24;
    size_t nodesMemory = row.size() * (sizeof(std::pair<std::string, SQLiteValue>) * nodePadding);
    return bucketMemory + nodesMemory;
  }

  /**
   * Compute the approximate external memory size of the full result set.
   * We add:
   * - The vector's backing storage,
   * - All rows (column names + values).
   */
  size_t getResultsExternalMemorySize(const SQLiteQueryResults& results) {
    size_t size = sizeof(SQLiteQueryResults);

    const auto resultCapacity = results.capacity();
    size += resultCapacity * sizeof(SQLiteQueryResultRow);

    for (const auto& row : results) {
      size += getRowExternalMemorySize(row);
    }

    return size;
  }

  /**
   * Compute the approximate external memory size of the table metadata.
   * We include:
   * - Column name string capacities (map keys),
   * - Metadata contents, especially the `name` string on each metadata entry.
   */
  size_t getMetadataExternalMemorySize(const SQLiteQueryTableMetadata& metadata) {
    size_t size = 0;

    for (const auto& [columnName, columnMeta] : metadata) {

      size += columnName.capacity();
      size += columnMeta.name.capacity();
    }

    return size;
  }

} // namespace

std::optional<double> HybridNitroSQLiteQueryResult::getInsertId() {
  return _insertId;
}

double HybridNitroSQLiteQueryResult::getRowsAffected() {
  return _rowsAffected;
}

SQLiteQueryResults HybridNitroSQLiteQueryResult::getResults() {
  return _results;
};

std::optional<SQLiteQueryTableMetadata> HybridNitroSQLiteQueryResult::getMetadata() {
  return _metadata;
}

size_t HybridNitroSQLiteQueryResult::getExternalMemorySize() noexcept {
  size_t size = sizeof(*this);

  size += getResultsExternalMemorySize(_results);

  if (_metadata) {
    size += getMetadataExternalMemorySize(*_metadata);
  }

  return size;
}

} // namespace margelo::nitro::rnnitrosqlite