KR20060078185A - Information searching system for car navigation system - Google Patents

Abstract

The present invention relates to a method and apparatus for searching a point of interest (POI) database of a user in a car navigation system. Especially, a quick search result using less resources when searching for a large amount of POI. It relates to an information retrieval system of a vehicle navigation system.

The information retrieval method of the vehicle navigation apparatus of the present invention is a general index for numerical data and an index for an unaligned name (string) in order to search for necessary information in a POI DB. A preprocessing step of generating an inversed file index; Determining an input search condition and searching and outputting corresponding information in a POI DB based on an inversed file index when the name is a single search; Determining an input search condition and retrieving and outputting corresponding information from a POI DB based on an index file for the numerical data in a case other than a name search alone; By performing a search, including, a high-speed information search is possible, and the performance of the search system is improved.

Vehicle Navigation System, Information Search, Search Engine

Description

Information retrieval system of vehicle navigation system {INFORMATION SEARCHING SYSTEM FOR CAR NAVIGATION SYSTEM}

1 is a block diagram showing the configuration of an information retrieval system of a vehicle navigation system according to the present invention;

2 is a diagram showing an example of an index of a general book for explaining the present invention;

3 is a diagram showing the configuration of a POI_DB and a general index file for numerical data according to the present invention;

4 is a diagram illustrating an example of a process of extracting a sub string from a POI name and sorting in alphabetical order while eliminating duplication;

FIG. 5 is a view showing an example of a name file (inversed file) recording a POI location including each substring in the present invention. FIG.

6 is a flowchart of the information retrieval method of the vehicle navigation apparatus according to the present invention.

<Explanation of symbols for the main parts of the drawings>

100: user search condition input unit 200: data storage unit

300: POI search engine 400: search result output unit

The present invention relates to a method and apparatus for searching a point of interest (POI) database of a user in a car navigation system. Especially, a quick search result using less resources when searching for a large amount of POI. It relates to an information retrieval system of a vehicle navigation system.

Recently, the popularity and demand of vehicle information terminals such as car navigation systems and telematics systems are increasing. In general, the vehicle navigation apparatus detects the current position of the vehicle on the basis of the position information received from the GPS, and based on the geographic information mapped therein, the information about the current geographical position of the vehicle and the road driving information to the destination are displayed. As a system to provide, various types and types of terminal apparatuses are provided. The telematics system also provides information on road conditions based on the location of the vehicle, as well as providing interactive information on the status and safety of the vehicle, exchanges, and a variety of geographical, physical and social environmental and environmental information. It is spreading as an advanced mobile communication terminal service provided.

Such a vehicle information terminal is basically a module for receiving and processing location information, a module for communication with a service system, a module for displaying information provided from a service system, a module for controlling them, a user or various sensors It is configured to include a module for interfacing with the module. The vehicle information terminal receives the GPS information from the GPS satellites to determine the current position, and based on the determined position information, various information provided from the service system, for example, navigation related information (map, road condition or delay / Congestion, etc.) and surrounding physical and social and environmental information (gas stations, restaurants, lodging establishments, tourist attractions, etc.) to provide a variety of information necessary for the user.

In order to receive directions in such a vehicle navigation system, a destination search and setting should be possible. However, in the case of a service system in which a call center is operated together, directions are mainly received through a telephone call with an agent. However, in most vehicle navigation systems, a navigation point or a telematics terminal itself has a location of interest database (POI DB: Points). Of Interest Data Base) is constructed, and the user searches the terminal directly to determine the destination.

Therefore, the question of how quickly the POI DB can retrieve information such as the desired destination acts as a factor in determining the performance and quality of the system.

In the case of POI DB, one set is composed of [name, location, industry code, area code], and this set is composed of hundreds of thousands or more to form the entire database. Here, each database type is composed of [String, Integer, Integer, Integer], and taking the combination of conditions that can be entered as an example: 1. Industry alone (search), 2. Region alone (search), 3. There are seven conditions: name alone (search), 4. sector + region (search), 5. sector + name (search), 6. region + name (search), 7. sector + region + name (search).

As the number of POIs increases as society develops and becomes more complex, new POIs will continue to increase, so that the storage medium capacity of the terminal will continue to increase, but the POI DB will be embedded in the terminal. Embedded systems have limited resources (storage capacity), unlike typical PC environments. Therefore, when performing a search on a large POI database in an embedded system, a well-defined search method is developed according to the structure of the POI database and its contents in order to improve search performance. Required.

Means of searching the POI DB in the conventional vehicle navigation apparatus may be as follows. The first is using a commercially available database management system, and the second is a method of linearly searching a flat file to produce a desired result.

 In the former case, most commercial database management systems (DBMSs) do not use the features of flash memory, which is a storage medium, such as a slow data read speed and a fast seek speed. It is intended for general use for the enterprise. When it's already created and used in an enterprise environment, and it's decided to put it in an embedded system, reduce the number of Structure Query Language (SQL) syntax available, or remove the indexing feature. In many cases, it's reduced functionality to make it suitable only for small database searches. Therefore, in many cases, the characteristics of the flash memory are not considered at all. For example, IBM's embedded DBMS, DB2e, is a scaled-down version of DB2 features built for the enterprise. This not only provides indexes for numeric data, but also does not support much of the functionality of SQL.

In the case of commercial DBMSs, adding indexes requires indexing according to the number of cases in the seven combinations of conditions described above. As a result, the amount of flash memory used to describe the index also increases exponentially, making it unsuitable for embedded systems with limited memory resources.

In addition, from the flash memory point of view, since the read speed is relatively slow, the search speed is remarkably slowed as the number of reads increases. However, the existing search apparatuses do not take this feature into account and simply repeat reading and comparing operations, thereby increasing the number of reads and the amount of read memory, thereby reducing the overall search performance.

Next, the flat file system linear search reduces the time spent parsing and executing the query, which can reduce the cost of time, but does not allow you to sort files that are not sorted according to their conditions. In the case of searching, it is inevitably read from the beginning to the end of the file and compared directly, so the search speed becomes slow in proportion to the amount of data.

In the conventional retrieval apparatus described above, after sorting and storing data, an index may be generated for the first value for each section (information storage section) through preprocessing. This indexing function provided by the existing device is suitable for numerical data, so it is suitable for searching 'industry' and 'region code' expressed in sorted numeric form, but in case of 'name (string)', the name alone Sorting the data according to the POI name in order in case of a condition is that the sorting order of the industry and area codes is out of order, thereby decreasing the efficiency of searching for other conditions.

The problems of the prior art described so far are as follows. First, commercial DBMSs are not suitable for embedded large database searches. Second, index functions can be used, but they are suitable for numerical data. There is a problem in that an index on a string is required, and the efficiency of other conditional searching is reduced, and, thirdly, the read memory is slow and the search speed does not consider the features of the flash memory.

Therefore, there is a need for a means to solve this problem and to derive faster search results in all combinations of search conditions.

SUMMARY OF THE INVENTION An object of the present invention is to provide an information retrieval system of a vehicle navigation apparatus which can search for necessary information in a POI DB at a high speed in a vehicle navigation apparatus.

It is still another object of the present invention to construct an index file for sorted numerical data and an index file for unaligned names (strings) in order to search for necessary information in a POI DB at high speed. The present invention provides an information retrieval system for a vehicle navigation system capable of improving the performance of a retrieval system by retrieving necessary information from a database of a storage medium based on the index file according to an input search condition.

In order to achieve the above object, the information retrieval method of the vehicle navigation apparatus of the present invention includes an unindexed name and a general index for numerical data in order to retrieve necessary information in a POI DB. A preprocessing step of creating an inversed file index for the (string); Determining an input search condition and searching and outputting corresponding information in a POI DB based on an inversed file index when the name is a single search; Determining an input search condition and retrieving and outputting corresponding information from a POI DB based on an index file for the numerical data in a case other than a name search alone; Characterized in that configured to include.

In addition, the information search apparatus of the vehicle navigation apparatus of the present invention for achieving the above object, the search condition input unit for inputting a search condition of the user; Data storing POI DB, general index for numerical data in POI DB, and inversed file index for unaligned names Storage unit; A POI search engine that searches for and outputs necessary information in a POI DB by referring to a corresponding index file of the data storage unit according to a search condition input through the search condition input unit; A search result output unit displaying the search result; Characterized in that configured to include.

In addition, in the information retrieval system of the vehicle navigation apparatus of the present invention, the retrieval condition is characterized in that it is a single retrieval of [region, industry, name] or a combination retrieval thereof.

In addition, in the information retrieval system of the vehicle navigation system of the present invention, the general index for the numerical data is arranged in the area of the industry after sorting the original data consisting of [region, industry, name] according to the area code POI DB is constructed by sorting according to codes, and based on the POI DB, only the first location of each region and the industry type code value is found and sorted.

In addition, in the information retrieval system of the vehicle navigation apparatus of the present invention, the inversed file index for the unordered name (string) is extracted without duplication of all names based on the POI DB, all extracted names Decomposing the substring into words and storing them in alphabetical order without duplication; comparing the stored substrings with each set of the POI DB, and when the substring is included as a partial string in the POI name, the corresponding substring is stored. It is characterized by generating the location information of the set including itself after the data structure.

In addition, in the information retrieval system of the vehicle navigation system of the present invention, the lower character string is characterized by selecting two or more characters.

In the information retrieval system of the vehicle navigation apparatus of the present invention, when the input search condition is a name-only search, a corresponding index file is read in block units to perform a comparative search.

In addition, in the information retrieval system of the vehicle navigation apparatus of the present invention, the substring of the search condition (name) is characterized in that the search based on the binary search.

In addition, in the information retrieval system of the vehicle navigation system of the present invention, if the search condition is a region alone condition or a combination of region and name, the POI DB is directly accessed based on the starting position of the region in the corresponding index file. It reads until the area code is changed and outputs the search result. When considering the condition of the name, information satisfying the corresponding name is output as the search result.

In addition, in the information retrieval system of the vehicle navigation apparatus of the present invention, if the search condition is a sole industry condition or a combination of the industry and name, POI based on the start position of the industry code for each region in the corresponding index file (general index) Directly access the DB and output as a search result, and when considering the name condition, it is characterized by outputting the information that satisfies the corresponding name as a search result.

In addition, in the information retrieval system of the vehicle navigation system of the present invention, when the search condition is a combination of the type of industry and region, or a combination of the type of industry and the region and name, the location of the type of business of the corresponding region in the general index file Find and output POI DB as a search result and output information that satisfies the corresponding name as a search result when considering the name condition.

An embodiment of the information retrieval system of the vehicle navigation apparatus of the present invention configured as described above will be described with reference to the accompanying drawings.

1 is a block diagram of an information retrieval system of a vehicle navigation system according to the present invention. As shown in FIG. 1, an information retrieval system of a vehicle navigation apparatus according to the present invention includes: a search condition input unit 100 for inputting a search condition of a user; Stores a POI database (POI_DB.dat), an index file (general_index.dat) for numerical data in the POI database, and an index file (inversed_file_index.dat) for an unordered name A data storage unit 200; A POI search engine 300 for searching for and outputting necessary information in a POI DB by referring to a corresponding index file of the data storage unit according to a search condition input through the search condition input unit 100; And a search result output unit 400 in which the search result is displayed.

When the user inputs three conditions of 'region', 'industry', and 'name' alone or freely through the search condition input unit 100, the POI search engine 300 stores the data according to the input search condition. The corresponding data is searched in the POI DB (POI_DB.dat) based on the index files of the unit 200, and the search result is displayed through the search result output unit 400. If the search condition is a name-only search, the information is read and output from the POI DB using the index file (inversed_file_index.dat) for the name. Otherwise, the index file (general_index) for numeric data is output. .dat) to read and output the information in the POI DB.

The index file (general_index.dat) for the numerical data and the index file (inversed_file_index.dat) for the name are generated by the preprocessing process described later and stored in the system. For numerical data, it has an index indicating the location of the data, and for its name, it has a file (inversed_file_index.dat) for that string, similar to the index on the back of a typical book, as shown in Figure 2. It will play a role. In other words, like an index (page notation) of a general book indicating the position of a word, the index has a name (string) and a location where information corresponding to the name (string) is stored.

The indexes are constructed not only for high-speed search, but also because the POI DB storage medium uses flash memory's slow read speed and fast seek speed. In other words, it is possible to read a much smaller index file, obtain a location close to the user input search condition from the index, and then directly access a desired location and read only the minimum data necessary, thereby greatly reducing the read speed.

The generation of the index files by the preprocessing process is performed before being stored in the real system. Unlike the real target system, the index files are executed on a high-performance platform such as a general PC. same.

[Preprocessing for Creating Index File]

FIG. 3 shows the configuration and interrelationship between the index file (general_index.dat) 210 and the POI DB (POI_DB.dat) 220 for numerical data in the information retrieval system of the vehicle navigation system of the present invention. The index file (general_index.dat) 210 for numerical data has index information on the start positions of sorted businesses, and this index information is information on the corresponding industry in POI_DB (POI_DB.dat) 220. Points to the starting position of. The information on the industry of the POI_DB (POI_DB.dat) 220 has a file 230 structure of [region, industry, name] and is configured for each industry and each industry corresponding to each area.

4 shows an example in which substrings are extracted from POI names and sorted in alphabetical order while removing their redundancy. In the POI_DB 240, the data 241 obtained by decomposing the name into the substring and the data 250 sorted in the lexicographic order while removing redundancy are shown. POI data listed according to actual region and industry, but only the name is considered here.

Fig. 5 shows an example 260 of an index file (inversed_file_index.dat) for a name that records the location of a POI including each substring. Here, the data structure is a structure representing an offset in POI_DB (POI_DB.dat) of the POI including the name.

These index files are organized as follows.

Step 1: Sort randomly collected raw POI data in ascending order according to the area code. And within the same region of the sorted data, sort in ascending order by industry code. As a result of this sorting, the region which is the primary criterion is sorted in ascending order, and the industry code is sorted in ascending order in each region. However, names do not have a particular order, so they are sorted by region and industry code. Referring to the database (POI_DB.dat) 220 illustrated in FIG. 3, the primary sorting is performed in the order of region 1, region 2, ..., region m as a result sorted in ascending order according to the region code. Again, within each region, you can see that the secondary sorting was done in the order of Industry 1, Industry 2, ..., Industry n. However, you can see that the name is not. For example, looking at sector 1 of region 1, it can be seen that there is no arrangement of names in the corresponding information structure 230, but arranged with the structure of [region 1, sector 1, name].

Second step: Based on the POI_DB (POI_DB.dat) 220 generated in the first step, only the first position of each region and the industry code value within the region is found and sorted in ascending order. As a result of this sorting, an index file (general_index.dat) 210 for numerical data is generated as illustrated in FIG.

That is, the index file (general_index.dat) 210 for the generated numerical data is an information structure indicating the location n of the industry m of the region m with respect to the POI_DB (POI_DB.dat) 220.

Step 3: This step extracts all names without duplication based on the POI_DB (POI_DB.dat) 220, decomposes them into substrings again, and then stores the decomposed strings in alphabetical order without duplication. Steps are performed as follows.

Based on the database (POI_DB (POI_DB.dat)) created in the first step, all the 'names' are extracted without duplication (that is, if the same name is found several times, it is unified and stored as one). Next, the extracted name is decomposed into substrings of all words and stored in alphabetical order without duplication. In other words, when the same sub string is found several times, the same sub string is stored unified. In the present invention, two or more letters are used as the sub string.

For example, as shown in FIG. 4, the names of 'LG Electronics', 'Samsung Electronics', 'Daewoo Motor' and 'Hyundai Motor' can be extracted by extracting the 'name' from the POI_DB 240 without duplication. . This means that even if there are two or more pieces of information named 'LG Electronics' in any region m (or an industry n in any region m), they are stored in a single name 'LG Electronics'. This 'name' is decomposed into substrings of all words. The decomposed string is indicated by the symbol '241'. The decomposed strings are sorted and stored in alphabetical order without duplication. After deduplication, the strings arranged in alphabetical order are denoted by the symbol '250'. Of course, this is the POI data listed according to the actual region and industry, but in Figure 4 is expressed only considering the 'name'.

Step 4: This step is to construct an indexed file (inversed_file_index.dat) for the name. The substrings extracted in the third step are sequentially extracted and compared with each set of the POI_DB (POI_DB.dat) 220 constructed in the first step. If the substring to be compared is included in the POI_DB (POI_DB.dat) 220 name as a part of the string, the position of the set containing the substring after the data structure where the substring is stored, that is, in the file Link the offset of the link to a linked list. If there are many sets containing the reference substring, make sure they have offsets after them.

An example of the index file (inversed_file_index.dat) generated by this step is shown in FIG. An example of the index file shown in Fig. 5 is a file in which the position of the POI including each substring is recorded, and the offset (name) represents an offset in POI_DB of the POI including the name.

If the user inputs "electronic" as a search condition, the user has the offset of "LG Electronics" and "Samsung Electronics", so he can directly access POI_DB and get the search results. That is, in the index file (inversed_file_index.dat) 260 illustrated in FIG. 5, the index information having 'electronic' as a string is described as [electronic-> offset (LG electronic)-> offset (Samsung electronic)]. With the offset, POI_DB (POI_DB.dat) (220) can be accessed directly to the places where the names 'LG Electronics' and 'Samsung Electronics' are located, and the result can be obtained. By extracting substrings from POI names, deduplicating them, decomposing them, and having files sorted in alphabetical order, the naming condition is not a complete name, but a substring of the name is provided as a search condition to provide a basis for searching. It becomes possible.

When the preprocessing process described above is performed, the following three files which are actually used in the information retrieval system of the vehicle navigation system are generated.

One is POI_DB (POI_DB.dat) 220 which is a search target as a result of the first step, and the other is for numerical data having respective starting positions of the numeric data generated as a result of the second step. An index file (general_index.dat) 210, and the other is an index file (inversed_file_index.dat) 260 of information related to the location of the sub-string resulting from the fourth step and the location of the POI including the same. to be.

Based on the file generated as described above, according to the search condition input, the corresponding information is searched in the POI_DB (POI_DB.dat) using an appropriate index file.

[Inquiry process based on user input search condition]

When the user inputs three conditions of [region, type of business, name] alone using the search condition input unit 100, or inputs a combination thereof as a search condition, the POI search engine 300 stores the data storage unit. Search for the corresponding information in POI_DB (POI_DB.dat) by referring to the appropriate index file among index files (general_index.dat) and numerical index files (inversed_file_index.dat) for numerical data stored in (200). The result is displayed on the output unit 400.

Figure 6 shows an embodiment of such a search method of the present invention.

First, a search condition input step S10 is a step in which a user inputs a search condition through the search condition input unit 100. As described above, the search condition may be three independent condition inputs of a region, an industry, and a name, or a condition input by a combination thereof. The POI search engine 300 according to the present invention performs a search using an appropriate index file for each case of a name-only condition and another case or a compound condition.

In the search condition determination step (S20), the search condition input by the user is determined. If the search condition entered by the user corresponds to the name-only search, the process proceeds to the next step (S31), and a set of substrings in the index file (inversed_file_index.dat) for the name is a block of each flash file system. Read into memory as much as a unit. The reason for reading in units of blocks in the flash file system is that even if the application reads in smaller units, the unit reads in units of blocks. Therefore, reading in blocks is most efficient.

In the next step S32, it is determined whether the input value (name entered as a search condition) is included in the read block range. If the name entered as the search condition is included in the read block range, the process proceeds to the next step S33, where a binary search is performed on the already sorted data in memory, and a binary search result substring is determined. . As described above, if a binary search is performed on data that is already sorted in memory, even if the amount of data is large, the number of comparisons is limited, thereby minimizing the number of comparisons of actual comparison data. In other words, when the number of data is n, the number of comparisons does not exceed log ₂ n, so the number of data comparisons and reads can be significantly reduced. Therefore, binary search is performed to find the input substring.

For example, in the example illustrated in FIG. 3, the number of POIs 240 is only four, but four data leads and four comparisons are required to find a word including 'car'. In other words, the number of times of data read and comparison becomes <4,4>. However, if the location of the index file (inversed_file_index.dat) 260 is found in advance, the index file reads and compares as well as the reads in the index file (POI_DB.dat) 220 twice. , 1>. Therefore, in the case of actually having tens or millions or more of data, when the redundancy of the substring increases exponentially, the number of data reads and comparisons is linearly read from hundreds of thousands, millions, to hundreds, hundreds. It will be reduced to a degree, which means an increase in search performance and speed. This shows that reading the indexed file (inversed_file_index.dat) for a name is several thousand to many tens of thousands of times more advantageous than a linear search.

On the other hand, if the result of the binary search in the binary search step (S33), if the lower string is not found, the process proceeds to the next step (S34) to determine whether there are more parts to read, and if there are more parts to read, the previous step (S31) ) And repeat the subsequent steps.

However, if the binary search result in the binary search step (S33), if the lower string is found, the process proceeds to the next step (S50) and outputs the result to the output unit 400 and proceeds to the search completion step (S60).

If the binary search result does not come out even though there are no more parts to read by repeating the series of steps described so far, the process proceeds to the step of outputting a search failure (S70) and the search ends.

On the other hand, in the search condition determination step (S20), if the search condition entered by the user is other than the name alone condition, the process proceeds to the next step (S41) to the local industry in the index file (general_index.dat) for the numeric data; The correct position is found and immediately read as needed from POI_DB (POI_DB.dat), and it is determined whether there is a result in the next step (S42). If there is no search result, the process proceeds to step S70 of outputting a search failure, and if there is a search result, the process proceeds to output step S50 of the result.

The input search condition and the corresponding search procedure in the above-mentioned information search based on the index file (general_index.dat) for numerical data can be classified into the following three cases.

The first is the case of local singular conditions or a combination of local and name search conditions. In this case, find the starting position of the region in the index file (general_index.dat) 210 for the numerical data, and immediately access POI_DB (POI_DB.dat) 220 to read the information until the region code is changed and return the result. Output If a name condition is added at this time, the search result is output when the name is satisfied.

The second case is the case of industry alone or a combination of industry and name. In this case, the index file (general_index.dat) (210) for numerical data is searched for the location of the industry code for each region, and the POI_DB (POI_DB.dat) 220 is directly accessed to read information satisfying the conditions. Output as a search result. Of course, in this case, if a naming condition is added, the search result is output when the name is satisfied.

The third case is a combination search condition of an industry type and a region or a combination search condition of an industry type and a region and a name. In this case, by referring to the index file (general_index.dat) 210, the location of the corresponding industry is immediately found in the corresponding area, and the POI_DB (POI_DB.dat) 220 is accessed and output as a result. In this case, if a naming condition is added, the result is output when the name is satisfied.

In the information search based on the index file (general_index.dat) for the numeric data described so far, only the necessary information can be read through the index file search and the search efficiency is high, and the search speed and performance are improved. This will be achieved.

The information retrieval system of the vehicle navigation apparatus of the present invention provides a fast information retrieval basis based on an index for sorted numerical data and an index for an unaligned name (string). Therefore, when the flash memory is used as a storage medium, the amount of flash memory is reduced and the search time is proportionally increased according to the data, so that the search can be performed within a relatively constant time.

In addition, according to the information retrieval system of the vehicle navigation system of the present invention, it is possible to improve the search performance by high-speed information retrieval, and the search time is leveled, thereby improving the quality of the vehicle navigation system. In addition, user interactivity may be improved.

Claims (15)

A preprocessing step of generating a general index for numerical data and an inversed file index for unaligned names (strings) to search for necessary information in a POI DB; Determining an input search condition and searching and outputting corresponding information in a POI DB based on an inversed file index when the name is a single search; Determining an input search condition and retrieving and outputting corresponding information from a POI DB based on an index file for the numerical data in a case other than a name search alone; Information retrieval method of the vehicle navigation apparatus characterized in that it comprises a. The method of claim 1, wherein the search condition is a single search of [region, industry, name] or a combination search thereof. The method of claim 1, wherein the general index of the numerical data is a POI DB by sorting the original data consisting of [region, industry, name] according to the area code and sorting according to the industry code within a region. And constructing by finding and aligning only the first position of each region and a sector type code value in the region based on the POI DB. The method of claim 1, wherein the inversed file index for the unsorted name (string) is extracted without duplication of all names based on the POI DB, and the extracted name is decomposed into substrings of all words. Storing the sub-strings in alphabetical order without duplication, and comparing the stored sub-strings with each set of the POI DB, if the sub-string is included as a partial string in the POI name, the sub-string is included after the stored data structure. And generating the position information of the set information. The information retrieval method of claim 4, wherein the lower character string selects two or more characters. The method of claim 1, wherein when the input search condition is a name-only search, an inversed file index is read in block units to perform a comparative search. The method of claim 1, wherein the substring of the search condition (name) is searched based on a binary search. The method of claim 1, wherein when the search condition is a region-only condition or a combination of region and name, until the region code is changed by directly accessing the POI DB based on the starting position of the region in the general index file. The information search method of a vehicle navigation system, characterized in that to read and output as a search result, the information that satisfies the corresponding name is output as a search result when considering the name condition. The method of claim 1, wherein the search condition is an industry-only condition or a combination of an industry type and a name, and the POI DB is directly accessed based on the start position of the industry code for each region in the corresponding index file. If the name condition is considered, the information search method for a vehicle navigation system, characterized in that for outputting information that satisfies the corresponding name as a search result. The method of claim 1, wherein when the search condition is a combination condition of an industry type and an area or a combination condition of an industry type and an area and a name, the location of the type of business in the corresponding region is found in the general index file to directly access the POI DB The information search method of a vehicle navigation system, characterized in that outputted as a search result, and outputting information that satisfies the corresponding name as a search result when considering the condition of the name. A search condition input unit for inputting a search condition of a user; Data storing POI DB, general index for numerical data in POI DB, and inversed file index for unaligned names Storage unit; A POI search engine that searches for and outputs necessary information in a POI DB by referring to a corresponding index file of the data storage unit according to a search condition inputted through the search condition input unit; And a search result output unit for displaying the search result. 12. The information retrieval apparatus for a vehicle navigation apparatus according to claim 11, wherein the search condition is a single search of [region, industry, name] or a combination search thereof. 12. The method of claim 11, wherein the general index file for the numerical data comprises an information file indicating a first position of a region and a region type code value in a POI DB composed of [region, industry type, name]. Information retrieval device of the vehicle navigation system. 12. The method of claim 11, wherein the inversed file index for an unordered name (string) is a corresponding one on a POI DB that contains itself after a corresponding data structure comprising at least two or more partial strings of [name]. An information retrieval apparatus for a vehicle navigation system, characterized by comprising an information file describing set position information. The method of claim 11, wherein the search engine determines the input search condition and searches for and outputs corresponding information from the POI DB based on an inversed file index when the name is solely searched. In the case of other than the search, the information retrieval apparatus of the vehicle navigation apparatus, characterized in that the corresponding information is retrieved and output from the POI DB based on the general index of the numerical data.

Images