Method handle

ThirdParty/libproj/vtklibproj/src/networkfilemanager.cpp:203–203

    ~DiskChunkCache();

    sqlite3 *handle() { return hDB_; }
    std::unique_ptr<SQLiteStatement> prepare(const char *sql);
    bool move_to_head(sqlite3_int64 chunk_id);
    bool move_to_tail(sqlite3_int64 chunk_id);