void TabletReader::QueryWhere(const Query_Predicate &predicate, offsetType limit, std::function<void(const Record &)> callback) const {
BitArray bit_array = WhereClause(predicate);
Record record;
rocksdb::Status status;
rocksdb::Slice new_key;
std::string buffer;
bit_array.iterateSetBits(limit, [&] (uint64_t pos) {
new_key = ReadStoreKey::MaterializedRowKey(pos).ToSlice();
status = db_->Get(
env_->getReadStoreReadOptions(),
new_key,
&buffer
);
if (status.IsNotFound()) {
return;
}
if (!status.ok()) {
throw TabletLevelDbException{status};
}
record.ParseFromString(buffer);
callback(record);
});
}
void TabletReader::OrderBy(column_t column, std::function<void(const Record &)> callback) const {
std::string buffer;
Record record;
GetBitArrays(column, ReadStoreKey::EmptyColumnKey(column), ReadStoreKey::EmptyColumnKey(column + 1), [this, &record, &buffer, &callback] (BitArray bit_array) {
bit_array.iterateSetBits(std::numeric_limits<offsetType>::max(), [&] (uint64_t pos) {
rocksdb::Status status = db_->Get(
env_->getReadStoreReadOptions(),
ReadStoreKey::MaterializedRowKey(pos).ToSlice(),
&buffer
);
if (status.IsNotFound()) {
return;
}
if (!status.ok()) {
throw TabletLevelDbException(status);
}
record.ParseFromString(buffer);
callback(record);
});
});
}
void TabletReader::QueryExactByColumn(column_t column, const std::string &value, std::function<void(const Record &)> callable) const {
rocksdb::Status status;
ReadStoreKey key{column, value};
std::string result;
status = db_->Get(env_->getReadStoreReadOptions(), key.ToSlice(), &result);
if (status.IsNotFound()) {
return;
} else if (!status.ok()) {
throw TabletLevelDbException{status};
}
BitArray bitArray;
bitArray.readStream(result.data(), result.size());
result.clear();
Record currentRecord;
bitArray.iterateSetBits(static_cast<offsetType>(-1), [&] (uint64_t pos) {
rocksdb::Slice newKey = ReadStoreKey::MaterializedRowKey(pos).ToSlice();
status = db_->Get(
env_->getReadStoreReadOptions(),
newKey,
&result
);
if (status.IsNotFound()) {
return;
}
if (!status.ok()) {
throw TabletLevelDbException{status};
}
currentRecord.ParseFromString(result);
callable(currentRecord);
});
}