Method Write

src/leveldb/benchmarks/db_bench_sqlite3.cc:474–575

  }

  void Write(bool write_sync, Order order, DBState state, int num_entries,
             int value_size, int entries_per_batch) {
    // Create new database if state == FRESH
    if (state == FRESH) {
      if (FLAGS_use_existing_db) {
        message_ = "skipping (--use_existing_db is true)";
        return;
      }
      sqlite3_close(db_);
      db_ = nullptr;
      Open();
      Start();
    }

    if (num_entries != num_) {
      char msg[100];
      snprintf(msg, sizeof(msg), "(%d ops)", num_entries);
      message_ = msg;
    }

    char* err_msg = nullptr;
    int status;

    sqlite3_stmt *replace_stmt, *begin_trans_stmt, *end_trans_stmt;
    std::string replace_str = "REPLACE INTO test (key, value) VALUES (?, ?)";
    std::string begin_trans_str = "BEGIN TRANSACTION;";
    std::string end_trans_str = "END TRANSACTION;";

    // Check for synchronous flag in options
    std::string sync_stmt =
        (write_sync) ? "PRAGMA synchronous = FULL" : "PRAGMA synchronous = OFF";
    status = sqlite3_exec(db_, sync_stmt.c_str(), nullptr, nullptr, &err_msg);
    ExecErrorCheck(status, err_msg);

    // Preparing sqlite3 statements
    status = sqlite3_prepare_v2(db_, replace_str.c_str(), -1, &replace_stmt,
                                nullptr);
    ErrorCheck(status);
    status = sqlite3_prepare_v2(db_, begin_trans_str.c_str(), -1,
                                &begin_trans_stmt, nullptr);
    ErrorCheck(status);
    status = sqlite3_prepare_v2(db_, end_trans_str.c_str(), -1, &end_trans_stmt,
                                nullptr);
    ErrorCheck(status);

    bool transaction = (entries_per_batch > 1);
    for (int i = 0; i < num_entries; i += entries_per_batch) {
      // Begin write transaction
      if (FLAGS_transaction && transaction) {
        status = sqlite3_step(begin_trans_stmt);
        StepErrorCheck(status);
        status = sqlite3_reset(begin_trans_stmt);
        ErrorCheck(status);
      }

      // Create and execute SQL statements
      for (int j = 0; j < entries_per_batch; j++) {
        const char* value = gen_.Generate(value_size).data();