cpp/src/reader/table_result_set.cc

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * License); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
#include "reader/table_result_set.h"

#include <utils/storage_utils.h>

namespace storage {
void TableResultSet::init() {
    row_record_ = new RowRecord(column_names_.size() + 1);
    pa_.reset();
    pa_.init(512, common::MOD_TSFILE_READER);
    index_lookup_.reserve(column_names_.size() + 1);
    index_lookup_.insert({"time", 0});
    for (uint32_t i = 0; i < column_names_.size(); ++i) {
        index_lookup_.insert({column_names_[i], i + 1});
    }
    result_set_metadata_ =
        std::make_shared<ResultSetMetadata>(column_names_, data_types_);
}

TableResultSet::~TableResultSet() { close(); }

int TableResultSet::next(bool& has_next) {
    int ret = common::E_OK;
    while (row_iterator_ == nullptr || !row_iterator_->has_next()) {
        if (RET_FAIL(tsblock_reader_->has_next(has_next))) {
            return ret;
        }

        if (!has_next) {
            if (row_iterator_) {
                delete row_iterator_;
                row_iterator_ = nullptr;
            }
            break;
        }

        if (RET_FAIL(tsblock_reader_->next(tsblock_))) {
            break;
        }
        if (row_iterator_) {
            delete row_iterator_;
            row_iterator_ = nullptr;
        }

        row_iterator_ = new common::RowIterator(tsblock_);
    }
    if (row_iterator_ == nullptr || !row_iterator_->has_next()) {
        has_next = false;
    }

    if (has_next && IS_SUCC(ret)) {
        uint32_t len = 0;
        bool null = false;
        row_record_->reset();
        for (uint32_t i = 0; i < row_iterator_->get_column_count(); ++i) {
            const auto value = row_iterator_->read(i, &len, &null);
            if (!null) {
                row_record_->get_field(i)->set_value(
                    row_iterator_->get_data_type(i), value, len, pa_);
                row_iterator_->next(i);
            }
        }
        row_iterator_->update_row_id();
    }
    return ret;
}

bool TableResultSet::is_null(const std::string& column_name) {
    auto iter = index_lookup_.find(column_name);
    if (iter == index_lookup_.end()) {
        return true;
    } else {
        return is_null(iter->second + 1);
    }
}

bool TableResultSet::is_null(uint32_t column_index) {
    ASSERT(1 <= column_index && column_index <= row_record_->get_col_num());
    return row_record_->get_field(column_index - 1) == nullptr ||
           row_record_->get_field(column_index - 1)->is_type(common::NULL_TYPE);
}

RowRecord* TableResultSet::get_row_record() { return row_record_; }

std::shared_ptr<ResultSetMetadata> TableResultSet::get_metadata() {
    return result_set_metadata_;
}

void TableResultSet::close() {
    tsblock_reader_->close();
    pa_.destroy();
    if (row_record_) {
        delete row_record_;
        row_record_ = nullptr;
    }
    if (row_iterator_) {
        delete row_iterator_;
        row_iterator_ = nullptr;
    }
}

}  // namespace storage