JP2009134298A - Navigation device and map data updating method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable updating of a map database readily in a navigation that has a rewritable storage medium and that obtains the latest map data to update a map database. <P>SOLUTION: The navigation device is provided with a map database that stores map data in a rewritable storage medium, and a map data managing means that carries out updating and searching of map data stored in the map database. The map data managing means manages the map data as a table which is classified by the attribute that shows additional information of a map element. Further, this table manages as a plurality of tables that are divided based on the update frequency of map elements, and at the time of map data updating, data update is carried out by the map element unit. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a navigation system, and more particularly to a system using a method of storing map data in a rewritable storage means and partially updating the map data.

  Navigation systems have emerged that store map data necessary for map display and destination search in a rewritable storage medium such as a hard disk or a removable memory.

  The map data provided to the navigation system becomes obsolete with the passage of time due to the latest facility information and the opening and closing of new roads. For this reason, a navigation system equipped with a hard disk is provided with a service for rewriting all map data by sending the disk to a dealer or manufacturer. The service has a problem that the device cannot be used until the disk is returned to the hand.

  On the other hand, a communication-type navigation system has appeared that transmits various useful information including map data to the vehicle navigation device by data communication between the navigation device mounted on the vehicle and the server device using the mobile phone network. ing. A method for updating the map data by receiving the latest map data from the server through communication is described in JP-A-9-145383, and as a navigation system for downloading map data from the server, for example, the description in JP-A-2003-42771 It has been known. Since the map data acquisition method by downloading from the server acquires the latest map data stored in the server, there is an advantage that the user can use the latest map data.

Japanese Patent Laid-Open No. 9-145383 JP 2003-42771 A

  However, in the conventional navigation system, map data is managed in the manufacturer's original data format, and the data is accessed by calculating the address from the top of the data file. For example, when updating some map data, It is necessary to generate updated map data depending on the sequence of data, and there is a problem that the latest map data cannot be used when the data format of the latest map data is changed or expanded, or in a device with a different format. . Further, the user or a third party cannot freely customize the data structure.

  In addition, since the file being updated cannot be referred to by other applications, functions such as map display and route search are not executed until the file update is completed, and the responsiveness of the map display and route search deteriorates. For example, if the display of the map is not updated at an appropriate timing during guidance, the original convenience of the navigation system that guides the user along a predetermined route is impaired.

  The object of the present invention is to obtain the latest map data without being limited to the map data format and use it for navigation such as destination setting, route search and guidance, and even when there are many update targets when updating data. An object of the present invention is to provide a navigation device that can suppress an increase in processing time.

  In order to solve the above problems, the present invention provides a navigation apparatus comprising a map database storing map data in a rewritable storage means, and a map data management means for updating and searching the map data stored in the map database. The map data management means manages the map data as a table classified by the attribute indicating the additional information of the map element, and manages this table as a plurality of tables divided based on the update frequency of the map element. In this case, data is updated in units of map elements.

  According to such a navigation apparatus, it is possible to partially update the map database, and therefore it is possible to suppress an increase in time required for the update process of the map database even when there is a lot of data to be updated.

  Embodiments of a navigation system using the present invention will be described below with reference to the drawings.

  FIG. 1 is a diagram showing the overall configuration of a navigation system using the present invention. The navigation system includes a navigation terminal 106 mounted on a vehicle 111 and a server apparatus 102 that receives / transmits data between the base station 104 and the navigation terminal 106 via the IP network 103.

  The server apparatus 102 includes map information, point information data such as restaurants and convenience stores, and traffic information data. The navigation terminal 106 has a function of acquiring map information such as the latest facilities and roads by accessing the server device 102, and calculating and guiding a route to the destination. The server apparatus 102 may include a route search engine. In this case, if there is a route search request from the navigation terminal 106, the server device 102 may execute a route search, return the result, and save the result in the server device 102 in some cases. Further, the server device 102 may search for point information data, traffic information data, etc. in response to a request from the navigation terminal 106 and return it.

  The configuration of the navigation terminal 106 in this embodiment will be described. The navigation terminal 106 includes a display device 302, a GPS (Global Positioning System) receiver 306, a main body 307, a hard disk device 309, a memory card slot 304, a mobile phone 303, a remote controller 305, and a microphone 308. The main body 307 is a device in which a CPU (arithmetic processing unit), a memory, a power source, and a graphics display device are mounted. In addition, the mobile phone 303 is used to transmit and receive data to and from the navigation server. The hard disk device 309 is a device for storing map data, accumulating received data from the server device 102, and loading information downloaded in the past onto the navigation terminal 106. A removable external storage device such as a memory card may be connected to the memory card slot 304 and map data may be stored similarly to the hard disk device 309 or received data from the server device 102 may be stored. If the hard disk device 309 stores map data and the removable external storage device such as the memory card stores data such as music and video, the user can share the memory card with other devices capable of playing music and video. Can be used.

  In the above-described configuration, the mobile phone 303 is used as a communication device with the navigation server, but another communication device, a PDA (Personal Digital Assistance), or a modem integrated with the main body 307 may be used. Information such as facilities, maps, area information, and entertainment information may be acquired by satellite broadcasting, wireless LAN using hot spots, and narrowband communication for vehicles DSRC (Dedicated Short Range Communications). Further, in-vehicle LAN (Local Area Network) can be connected instead of the mobile phone 303. Instead of the GPS receiver 306, a location identification service using a PHS (Personal Handyphone System) may be used.

  FIG. 2 is a diagram for explaining a functional configuration of a CPU (arithmetic processing unit) mounted on the main body 307, in particular, a function related to data update of the present invention. Hereinafter, the components will be described.

  The current position detection unit 405 sets the current position of the vehicle from the position data obtained from the GPS receiver 306. The main body 307 is equipped with a sensor for detecting the moving direction and moving distance of the vehicle by taking in the output data of the gyroscope and direction sensor and the vehicle speed sensor, and calculating the moving distance and traveling direction of the vehicle with reference to the sensor output. In addition, the current position until the next GPS data is received may be estimated. The input analysis unit 406 receives a user request from a device that can input a user request, such as the remote controller 305 and the microphone 308, analyzes the request, and controls each unit so that processing according to the request is executed. The communication processing unit 404 is connected to the mobile phone 303 and transmits / receives data to / from the server apparatus 102 via the public network. In addition to wired connection, infrared communication or wireless communication may be used for connection with the mobile phone 303.

  The database management unit 400 is a part of the basic functions of the database system. In order to efficiently access a map database stored in a storage medium such as a hard disk, the data read once is cached in the memory 408 for the second time. Subsequent processing to speed up data reading, transaction processing to monitor the completion of data update, exclusive control such as locking the record of the map data being updated, recovery in case of data failure by log or backup, map Management of index area used for data and map data search is executed. The data reading unit 410 sets an area necessary for display when the map display area is changed (scrolling or scale change) via the position information detected by the position detection unit 405 or the input analysis unit 406, and the database A display map data search command is issued to the management unit 400. The map data obtained as a result is notified to the display processing unit 407. The display processing unit 407 once renders the map in the memory 408 and displays the map on the display device 302. The update data acquisition unit 402 requests map data from the server apparatus 102 via the communication processing unit 404 and acquires map data for update. Information such as facilities input (added / deleted) by the user via the input analysis unit 406 may be acquired. The update data interpretation unit 403 interprets update procedure information and update procedures such as how to update update procedure information included in the acquired map data and which part of the map database. The database update unit 401 creates a command (search / insert / delete / content change) for accessing the map database according to the interpretation result, and notifies the database management unit 400 of the command. The update history management unit 409 records or reads a change history such as a change date and time or a location.

  FIG. 3 is a flowchart for explaining the data update of the map data in the navigation device, FIG. 3 (a) is a data update process, and FIG. 3 (b) is a flowchart of the individual data reflection process.

  First, the data update process of FIG. When updating the map data, the update data acquisition unit 402 determines where and what data is to be updated based on the user input obtained through the input analysis unit 406. A map data request command including a request condition specified by an area such as the periphery / destination area, a point such as the current location / route / destination, a data type such as facility data / road data, etc. is transmitted to the server apparatus 102 ( 500). The update data acquisition unit 402 receives the update data of the map data sent from the server apparatus 102 according to the transmitted request condition (501). The update data interpretation unit 403 performs individual data reflection processing for updating the map database based on the received update data of each map data (507). Then, it is determined whether processing has been completed for all update data (508). If update data remains, the next update data is read (509) and individual data reflection processing is performed (507). Execute until all the map elements included in are finished.

  As shown in FIG. 3B, the individual data reflection process first interprets the update procedure information included in the update data of the acquired map data, and the map data update method and procedure such as addition / deletion / content change, The map database table, record, and column (attribute) to be updated are specified (502). The database update unit 401 sets the specified table, record, or column as a search condition, creates a data update command for updating the map database based on the map data update method included in the update data, and the database management unit 400 This data update command is issued to (503). The database management unit 400 accesses the map database according to the received data update command, searches for a record to be changed, and executes data rewriting (504).

  Then, by referring to the location area of the update data (area such as city name) and location (505), a new record is added to the change history data table, and the location area and location of the reference result are updated, such as the update date and time, contents, etc. It is stored in the additional record in association with the update information (506). When the update of the map database is completed normally, an update history including detailed information such as update date / time, data version, and updater is recorded in the update history (505). The data update command generated by the database update unit 401 not only rewrites record data, but also generates a command for performing table management such as generation of a new table.

  In this way, by updating the map database by this method, the user can use the latest map data for navigation such as information search, map display, destination search, route search, and guidance.

  FIG. 4 is a configuration example of a map database of the navigation device. The structure of map data will be described using facility data as an example. As the types of map data, in addition to facility data, road data, route search data, VICS compatible data, and the like are classified according to the type of map data or purpose of use, and are managed as a separate table. In addition, local names, local government names, administrative division names, etc. common to these tables are managed as independent tables.

  As an example of the facility data table (600), a facility-specific ID, facility name, genre (type), position (coordinates such as latitude and longitude), evaluation, and memo are provided as columns (facility data attributes). ing. In addition to these columns, attributes such as telephone numbers, addresses, area names, regular holidays, business hours, reading data (names, addresses, etc.) can be extended as necessary. Each record constituting the table corresponds to a map element, and the attribute of the record is information corresponding to additional information of the map element. If the table is a road data table, the attributes include road types such as general roads, national roads, etc., road names (such as national highway No. 6), number of lanes (road width), road coordinate information, etc. To prepare. By doing so, the update map data and the update target of the map data before update (map elements such as facilities and roads) are compared as before, and the map data when the update target does not exist in the map data before update Since the map database can be partially updated according to the present invention even when the processing load for executing the comparison increases and the update time becomes longer, the map database can be partially updated. An increase in time can be suppressed, and a process for determining an update method in comparison with existing data is facilitated by an update procedure, so that the data update time is shortened.

  The index (601) is information for searching the facility data table (600) at high speed. For example, when a search is performed using the facility name as a key, the storage location of data is read in the order of the alphabetical order from the beginning of the facility name. Show. The index is created in advance and stored in the hard disk device 309 together with the map data. When the facility table is updated, it is necessary to reconstruct the index together. Contrary to the user's willingness to reflect in navigation processing such as destination search as soon as updated to the latest data, it may be possible to wait for the facility data search until the index update is completed. Therefore, frequently updated facility data (convenience stores, restaurants, etc.) is composed of a table separate from facilities with low update frequency (public facilities, etc.), and the index is enabled / disabled based on the update frequency. It is possible to change the index update timing. In this way, it is possible to prevent the search waiting time from becoming long by configuring the table according to the type of map data and adjusting the index update timing.

  For example, when searching for “Aoyama XX Hotel” using this table structure, the index (601) is sequentially traced from the top of the name reading data, and the name that matches the record in the data area indicated by the index is searched. That's fine.

  “Evaluation” of the table attribute indicates a subjective evaluation of the user with respect to the corresponding facility. As in this example, a comprehensive evaluation may be performed, or a plurality of “evaluation” items such as “taste”, “atmosphere”, and “price” may be provided. The “evaluation” may be a numerical value as in this example, or a character string such as “good”, “normal”, or “bad” may be used. Thus, by including user subjective information in the database, the user can search for desired facility information from subjective information such as a delicious store or a cheap store. If the search result is set as the destination, it is possible to guide to a “delicious restaurant”.

  When an attribute indicating subjective evaluation is provided in the road data table, records in the road data table are configured in units of road links, and landscape information such as “bad view” and “good scenery” is included in the attribute as user subjective information This makes it possible to realize a route search using attributes such as the visibility and the landscape as the route search conditions.

  FIG. 5 is a flowchart showing a procedure for acquiring data from the server and updating the map database based on the subjective information of the user.

  The navigation terminal 106 will explain an example in which the map data update request (500) is transmitted to the server apparatus 102 with the current location and “delicious shop” as the update condition. In the figure, “PoiUpdate” of the map data update request is a “map data update” request command, “clt” and “cln” are the latitude and longitude of the current vehicle position, and “rad” is the current position (clt, cln). The central search range (radius km) and “eval” are items representing the subjectivity of the user. Therefore, in the example of this figure, update data including “delicious shop” is requested to the user's subjectivity in the range of 10 km around the latitude = 1234, longitude = 5678.

  Upon receiving the map data update request (500), the server apparatus 102 executes a process of converting the value set in evak into a predetermined evaluation value (710). In this example, first, the phrase “delicious” representing subjectivity is extracted from the data “delicious shop” and converted into a predetermined evaluation value. In addition, a plurality of similar words (“delicious”, “recommended”, etc.) corresponding to “delicious” are created. Next, a command for searching the map database using the converted evaluation value or a plurality of similar words as a search key is generated (711). As a command for searching the database, SQL (Structured Query Language) is generally used. However, other command forms may be used as long as the command can search the database based on a predetermined key. In the present embodiment, it is assumed that the server apparatus 102 sets “delicious store” as an evaluation value of 3 or more in advance. Accordingly, the search condition is specified with an evaluation value of 3 or more, a center coordinate (clt, cln), and a radius of 10 km, and the database is searched (712). The server apparatus 102 creates update data for reply based on the result of searching the database (713).

  As the reply data, for example, XML (eXtensible Markup Language) is used as shown in the update data 740. “NewMapData” is the data structure of the facility data to be returned. The update procedure information is defined as a data structure. For example, the data structure of NewMapData is defined as “update, delete, insert”. This indicates that the map update data is composed of “content change data, deleted data, and newly added data”. Further, since the update data of the map is arranged in the order of “update, delete, insert”, the terminal updates the data in the order of content change data, deletion data, and newly added data corresponding to this. For the order of data update order, add the tag indicating the order to the facility data structure poi (for example, <order> update order </ order>) to directly indicate the update order of the corresponding facility data. You can also. By specifying the order of data update, data can be added with priority given to popular facilities and facilities with high utility value (e.g., facilities for children and persons with disabilities are enriched). Further, the same effect can be obtained by sorting the facility data poi in the descending order of priority of update in the server apparatus 102 that generates update data for reply.

  In this example, the method of instructing deletion or addition by defining update procedure information (addition, deletion, etc.) in the data structure of update data NewMapData was explained. However, update procedure information is defined in the data structure of facility data poi It doesn't matter. In this case, in addition to instructing insertion, update, and deletion of data, the update procedure information includes a plurality of processes such as calculating the “evaluation value” attribute value of the corresponding record when the corresponding facility information is updated. It is also possible to specify procedures that continue. An example is shown in FIG. When defined in this way, an update procedure can be instructed to each facility data (facility element), so that a detailed update instruction is given to the facility element, such as executing a predetermined calculation in accordance with the update of the predetermined attribute of the facility data become able to.

  In the example shown in FIG. 11, it is determined from the update procedure information tag “<command1>” that this update data is a content change (update) of the facility data, and the facility code (id) and facility name (name) Replace data with data in an existing map database. Then, the evaluation value is calculated according to the instruction to calculate the evaluation value of the facility data from the update procedure information command2 defined between the tags “<command2>” to “</ command2>”. For the calculation of the evaluation value, for example, the character strings “delicious” and “delicious” that can be converted into the evaluation value are extracted from the information attached to the attribute “memo”, and the evaluation value is determined according to the evaluation attribute specified by the evaluation display attribute 730 There is also a method of obtaining by converting to. Further, when there are a plurality of evaluation value items such as “taste” and “atmosphere”, a comprehensive evaluation value may be obtained from these values.

  The navigation terminal 106 receives the update data (740), acquires the update data (501), and determines whether the update data satisfies a data update condition set in advance in the navigation terminal 106 (720). Then, the map database is updated according to the individual data reflection process with reference to the data selected as the update target (721). For example, if “delicious store” has been searched with an evaluation value of 3 or more, but the user has set facility data with an evaluation value of 5 as a database update condition, the evaluation value is 5 from the update data 740 Individual data reflection processing is performed by selecting only facility data. Moreover, since the evaluation of the existing (pre-update) facility data in the map database may be changed, the facility data designated by update as the update method of the update data 740 can be considered as the update target. The user obtains the latest map data by inputting subjective information such as the current location (10km range) and "delicious shop", and navigation such as information search, map display, destination search, route search, guidance, etc. Map data updated for processing can be used.

  It is determined whether update processing has been completed for all selected update data (722). When all update processing is completed, the updated map data is displayed according to the display attributes set on the display attribute setting screen (730). 302 is displayed (724). In the example shown in FIG. 5, the facility display attribute (730) indicates that the evaluation display is “ON”, the displayed facility (or evaluation display) is “evaluation value 3 or more”, the display form is “★”, and the updated facility This means that the icon display “ON” is displayed. Display attributes such as display / non-display of update history information, color / line type / pattern / transparent mode, etc. are set on the display attribute setting screen (730) of the display attribute setting means, and updated based on the display attributes set thereby. History information will be displayed on the screen.

  FIG. 6 is a flowchart illustrating a procedure of subjective data update processing in which the input analysis unit 406 interprets user subjective information and updates data.

  A user instruction including a subjective expression such as “update the delicious restaurant nearby” is received via an input device such as the remote control 305, the touch panel, or the voice microphone 308 (800). Column) is extracted (801). Words corresponding to subjectivity (words represented by adjectives such as big, small, far, close, delicious, bad, etc.) are determined in advance, and words that match this are extracted from the sentence entered by the user. The extracted word (character string) is converted into a predetermined parameter according to the conversion value set in the user subjective conversion value setting (802) (803). For example, “delicious” is an evaluation regarding “taste”, an evaluation of “taste” of 2 or more is “delicious”, “close” is an evaluation regarding “peripheral distance”, and “peripheral distance” is within 10 km. The map data update request 500 is transmitted to the server apparatus 102 using the converted subjective expression as an update condition (804). Then, data update processing is performed according to the received update data (805), and after updating the map database, the facility data updated according to display attribute setting values set in advance is displayed (806).

  FIG. 7 shows an example of the display of the facility information updated in FIG. 5 and FIG. The display example screen (900) is a case where display of user subjective information is enabled. Reference numeral 901 denotes a vehicle position mark. It is assumed that the display attribute is set so that “delicious store” is represented by the number of ★ marks as user subjective information. In addition to “delicious”, the result of comprehensive evaluation of multiple evaluation items such as “atmosphere” and “price” may be expressed by ★ marks. In addition, the display attribute 730 is set to ON / OFF for each display of “delicious”, “atmosphere”, and “price”, or “delicious”, “atmosphere”, and “price” are switched by pressing a predetermined key. May be displayed. Also, other forms such as displaying each evaluation item in a chart format 903 may be used.

  Further, in this embodiment, by adding the data corresponding to the tag “<reason>” indicating the reason for updating to the facility data poi to be updated, information such as new opening, closing, and relocation of the corresponding facility is added. be able to. For example, the facility data added by opening a new store can be displayed with an icon 904 such as opening or moving. Here, the closed facility may be deleted from the database according to the update instruction delete, but if the attribute of the facility table 600 of the map database is expanded, the closed facility is displayed in a display form (color, transmission mode, × Etc.) can be displayed. Specifically, the facility state is newly added to the facility database 600 as an attribute, and the reason for the change such as a new store opening / closing / relocation is recorded in the facility state. When the facility information is displayed, the reason for the change is referred to, and the facility is displayed in a display form such as opening or closing depending on the reason. The closed facility may be deleted from the map database after a predetermined time has elapsed since the date and time when the map data was changed.

  By doing so, it becomes possible to acquire the latest facility data by specifying conditions such as “neighboring shops” and “delicious”. In addition, by defining new information that does not exist in the existing map data as the attribute of the corresponding map element and adding it to the update data format, the map database inside the navigation device is automatically updated when the map database is updated. Since it can be reflected, it is possible to easily add a new store to the map data and to make user-specific information such as a bite memo and subjective information invisible.

  FIG. 8 is a flowchart illustrating a change history display process in which the update history management unit 409 records or refers to a history and displays the change history.

  When updating the map database, the individual data reflection process shown in FIG. 3B refers to the location area and location of the update data (for example, the location of the update data 740) (505), and the database management unit 400 On the other hand, a new record is added to the change history data table recorded in the hard disk device 309, and the location area (area such as municipality name) and position are associated with update information such as update date / time and contents in the record. A command to store (506) is issued to the database management unit 400. Thereby, the update history of the map database is reflected in the change history data table.

  When the user inputs “update history display” in the state where the update of the map database has been completed for all the facility data of the update data (210), a change history data search command is issued to the database management unit 400 (211). Based on the change history data search command, the area information of the update history data is searched (212), the area information is referred to for all update records updated in the individual data reflection process (213), and becomes the update target. Drawing data is generated from the area information (214), and the change history is displayed on the display device 302 (215).

  FIG. 9 shows an example of a change history display based on the change history data. The display example of FIG. 9A is an example in which a place where data update has occurred in the past in Tokyo 23 wards is displayed on the screen 230 on the map together with the update date and time. The display example of FIG. 9B is an example in which a more detailed update history is displayed on the screen 240. Data updated in the past in Setagaya-ku is searched, and the update date and time (content update, addition) , Deletion, etc.), so that the facility name can be confirmed. By recording the update history data in association with the position on the map, the place updated in the past can be confirmed together with the detailed information such as the update date and time.

  FIG. 10 is a flowchart showing a process of executing map data update and data search based on a user operation situation. When the destination, waypoint, or route is determined in the navigation terminal 106 (1000), the destination, waypoint, or the periphery of the route is set as the update target area (1001). A distance obtained by referring to the user subjective setting 802 may be used for setting the update target area. Map data of the area is acquired from the server apparatus 102, and data update processing is performed (1002). Next, the database updating unit 401 issues a command for searching facility information around the destination, waypoint, or route to the map database management unit 400 (1003), and searches for the facility information (1004). The facility data obtained as a search result is cached in the memory 408 (1005).

  Predicts that the user will request information retrieval of facility data around destinations, waypoints, or routes while traveling, updating facility data in the map database in advance to the latest data, and an updated map database By searching the facility information from the cache and caching it in the memory, the user can perform basic navigation operations such as destination setting and route setting, so that the latest map data can be obtained without waiting for data update or search. Will be available.

  In the present embodiment, the method for acquiring update data via the communication means has been described. However, the map update data is stored in a removable storage medium such as a memory card, and the update data is read from the memory to store the map database. It may be updated.

  The present invention relates to a navigation device, and in particular, can be used as a navigation device that acquires update data and updates map data. Since the present invention acquires map data independent of the map data format and updates the map data, the user obtains desired update data by specifying conditions such as area and data type, information retrieval, destination It is possible to realize a navigation device that can be used for navigation such as setting and route guidance, and that can customize data reflecting user preferences.

It is a figure which shows the whole system of this invention. It is a figure which shows the function structure in connection with data update. It is a flowchart which shows the procedure which updates map data. It is a structural example of a map database. It is a flowchart which shows the procedure which updates map data with subjective information. It is a flowchart which shows the procedure which updates subjective data. It is an example of a display of the updated facility data and subjective information. It is a flowchart which shows the procedure which records and displays an update change log | history. It is a display example of an update history. It is a flowchart which shows the procedure which estimates and performs map data update and a search process from an operation condition. It is a figure which shows an example of the definition of an update procedure.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 102 ... Server apparatus, 103 ... IP network, 104 ... Base station, 106 ... Navigation terminal, 111 ... Vehicle, 301 ... GPS satellite, 302 ... Display apparatus, 303 ... Mobile phone, 304 ... Memory card slot, 305 ... Remote control, 306 ... GPS receiver, 307 ... main body, 308 ... microphone, 309 ... hard disk device.

Claims (3)

A map database storing map data in a rewritable storage means;
In a navigation device comprising map data management means for updating and searching map data stored in a map database,
The map data management means manages map data as a table classified by attributes indicating additional information of map elements, and manages the tables as a plurality of tables divided based on the update frequency of map elements. A navigation device characterized by updating data in units of map elements.   2. The map data management unit according to claim 1, wherein an index is provided for each of the divided tables, and the index update timing is changed by enabling or disabling the index based on an update frequency of the divided table. Navigation device.   In the map data management means, among the divided tables, at least one of the facility tables with high update frequency is a table of restaurant facility data, and at least one of the table of facility with low update frequency is: The navigation apparatus according to claim 1, wherein the navigation apparatus is a table of facility data of public facilities.

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