YugabyteDB (2.13.1.0-b60, 21121d69985fbf76aa6958d8f04a9bfa936293b5)

// Copyright (c) YugaByte, Inc.

//

// Licensed 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.

//

#ifndef YB_DOCDB_QL_STORAGE_INTERFACE_H

#define YB_DOCDB_QL_STORAGE_INTERFACE_H

#include <limits>

#include <string>

#include <type_traits>

#include "yb/common/common_fwd.h"

#include "yb/docdb/docdb_fwd.h"

#include "yb/docdb/ql_rowwise_iterator_interface.h"

#include "yb/util/monotime.h"

namespace yb {

namespace docdb {

// An interface to support various different storage backends for a QL table.

class YQLStorageIf {

 public:

  typedef std::unique_ptr<YQLStorageIf> UniPtr;

  typedef std::shared_ptr<YQLStorageIf> SharedPtr;

  virtual ~YQLStorageIf() {}

  //------------------------------------------------------------------------------------------------

  // CQL Support.

  virtual CHECKED_STATUS GetIterator(const QLReadRequestPB& request,

                                     const Schema& projection,

                                     const Schema& schema,

                                     const TransactionOperationContext& txn_op_context,

                                     CoarseTimePoint deadline,

                                     const ReadHybridTime& read_time,

                                     const QLScanSpec& spec,

                                     std::unique_ptr<YQLRowwiseIteratorIf>* iter) const = 0;

  virtual CHECKED_STATUS BuildYQLScanSpec(

      const QLReadRequestPB& request,

      const ReadHybridTime& read_time,

      const Schema& schema,

      bool include_static_columns,

      const Schema& static_projection,

      std::unique_ptr<QLScanSpec>* spec,

      std::unique_ptr<QLScanSpec>* static_row_spec) const = 0;

  //------------------------------------------------------------------------------------------------

  // PGSQL Support.

  // TODO(neil) Need to replace GetIterator(ybctid) with CreateIterator and InitIterator.

  // I leave Create and Init code here, so I don't have to rewrite them in the near future.

  //

  // - Replacement is not done yet because reusing iterator is not yet allowed. When reusing it,

  //   doc_key.get_next() asserts that an infinite loop is detected even though we're calling

  //   get_next() for a different hash codes.

  // - Create and init can be used to create iterator once and initialize with different ybctid for

  //   different execution.

  // - Doc_key needs to be changed to allow reusing iterator.

  virtual CHECKED_STATUS CreateIterator(const Schema& projection,

                                        const Schema& schema,

                                        const TransactionOperationContext& txn_op_context,

                                        CoarseTimePoint deadline,

                                        const ReadHybridTime& read_time,

                                        std::unique_ptr<YQLRowwiseIteratorIf>* iter) const = 0;

  virtual CHECKED_STATUS InitIterator(docdb::YQLRowwiseIteratorIf* doc_iter,

                                      const PgsqlReadRequestPB& request,

                                      const Schema& schema,

                                      const QLValuePB& ybctid) const = 0;

  // Create iterator for querying by partition and range key.

  virtual CHECKED_STATUS GetIterator(const PgsqlReadRequestPB& request,

                                     const Schema& projection,

                                     const Schema& schema,

                                     const TransactionOperationContext& txn_op_context,

                                     CoarseTimePoint deadline,

                                     const ReadHybridTime& read_time,

                                     const docdb::DocKey& start_doc_key,

                                     std::unique_ptr<YQLRowwiseIteratorIf>* iter) const = 0;

  // Create iterator for querying by ybctid.

  virtual CHECKED_STATUS GetIterator(uint64 stmt_id,

                                     const Schema& projection,

                                     const Schema& schema,

                                     const TransactionOperationContext& txn_op_context,

                                     CoarseTimePoint deadline,

                                     const ReadHybridTime& read_time,

                                     const QLValuePB& ybctid,

                                     std::unique_ptr<YQLRowwiseIteratorIf>* iter) const = 0;

};

}  // namespace docdb

}  // namespace yb

#endif // YB_DOCDB_QL_STORAGE_INTERFACE_H