49   Slice key;
50   Slice value;
64   virtual void Seek(const Slice& key) = 0;
66   virtual void SeekForPrev(const Slice& key) = 0;
107   Status Put(ColumnFamilyHandle* column_family, const Slice& key,
108              const Slice& value) override;
110   Status Put(const Slice& key, const Slice& value) override;
113   Status Merge(ColumnFamilyHandle* column_family, const Slice& key,
114                const Slice& value) override;
116   Status Merge(const Slice& key, const Slice& value) override;
119   Status Delete(ColumnFamilyHandle* column_family, const Slice& key) override;
120   Status Delete(const Slice& key) override;
124                       const Slice& key) override;
125   Status SingleDelete(const Slice& key) override;
129                      const Slice& /* begin_key */,  in DeleteRange()  argument
130                      const Slice& /* end_key */) override {  in DeleteRange()
134   Status DeleteRange(const Slice& /* begin_key */,  in DeleteRange()  argument
135                      const Slice& /* end_key */) override {  in DeleteRange()
141   Status PutLogData(const Slice& blob) override;
185                       const DBOptions& options, const Slice& key,
191   Status GetFromBatch(const DBOptions& options, const Slice& key,  in GetFromBatch()
207                            const Slice& key, std::string* value);
211                            const Slice& key, PinnableSlice* value);
214                            ColumnFamilyHandle* column_family, const Slice& key,
219                            ColumnFamilyHandle* column_family, const Slice& key,
224                               const size_t num_keys, const Slice* keys,
265                            ColumnFamilyHandle* column_family, const Slice& key,
269                               const size_t num_keys, const Slice* keys,