in tools/parquet-scan.cc [25:78]
int main(int argc, char** argv) {
if (argc > 4 || argc < 1) {
std::cerr << "Usage: parquet-scan [--batch-size=] [--columns=...] <file>"
<< std::endl;
return -1;
}
std::string filename;
// Read command-line options
int batch_size = 256;
const std::string COLUMNS_PREFIX = "--columns=";
const std::string BATCH_SIZE_PREFIX = "--batch-size=";
std::vector<int> columns;
int num_columns = 0;
char *param, *value;
for (int i = 1; i < argc; i++) {
if ((param = std::strstr(argv[i], COLUMNS_PREFIX.c_str()))) {
value = std::strtok(param + COLUMNS_PREFIX.length(), ",");
while (value) {
columns.push_back(std::atoi(value));
value = std::strtok(nullptr, ",");
num_columns++;
}
} else if ((param = std::strstr(argv[i], BATCH_SIZE_PREFIX.c_str()))) {
value = std::strtok(param + BATCH_SIZE_PREFIX.length(), " ");
if (value) {
batch_size = std::atoi(value);
}
} else {
filename = argv[i];
}
}
try {
double total_time;
std::clock_t start_time = std::clock();
std::unique_ptr<parquet::ParquetFileReader> reader =
parquet::ParquetFileReader::OpenFile(filename);
int64_t total_rows = parquet::ScanFileContents(columns, batch_size, reader.get());
total_time = static_cast<double>(std::clock() - start_time) /
static_cast<double>(CLOCKS_PER_SEC);
std::cout << total_rows << " rows scanned in " << total_time << " seconds."
<< std::endl;
} catch (const std::exception& e) {
std::cerr << "Parquet error: " << e.what() << std::endl;
return -1;
}
return 0;
}