JP5338260B2 - Data list read / write device and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform reading/writing by reducing memory capacity for storing pieces of data or records and minimizing deterioration of a response of the reading. <P>SOLUTION: In this data list reader/writer which reads many pieces of data stored according to an application 2, and sequentially writes desired pieces of data to create a freely readable specific data list, a plurality of pieces of data are sequentially stored in specific positions without associating offsets with them in a storage part 5 of data without offset, the offsets are associated with an offset table 6 which is linked to the storage part 5 of the data without offset at predetermined data intervals, and when the desired pieces of data are selected from the specific data list, a nearby offset is selected from the offset table 6, the number of pieces of data is calculated to the number of desired pieces of data based on the offset, the desired pieces of data are read from a reading/writing part 7, a memory region for information on the offset is omitted, the memory capacity can be reduced, the response which hardly makes a person recognize a sense of incongruity of deterioration of the response is attained. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a data list reading / writing apparatus and method for extracting and creating a list according to a specific purpose from a large number of data and records. For example, the name, address, etc. of in-vehicle navigation for guiding a vehicle to a destination This relates to the handling of a large number of data and records for creating a specific list used for destination search.

FIG. 6A is a conceptual diagram of a list example in which conventional data is stored, and FIG. 6B is a conceptual diagram of a modified example of a list in which conventional data is stored.
In general, data and records that are continuously stored are written as offset information along with the data and records, as shown in the example of the list in FIG. Stores offset information that can refer to the beginning of data. As a result, when it is desired to refer to the previous data or record, the next moving position can be identified and the target data can be acquired using the offset information to the previous data and record.

Patent Document 1 is known as this type of data list read / write device. In addition, the number in the following () shows the component as described in drawing of patent document 1. FIG.
In the data list reading / writing device of Patent Document 1, the offset generation unit (13) analyzes the structured data (3) input from the application (2), and determines the offset position of a specific data element in the structured data (3). Calculate to generate offset information indicating the offset position of the data element, and the storage unit (14) includes the offset information in the structured data (3) and stores it as structured data with offset (4). When the input unit (1101) of the control unit (11) receives an acquisition request for a specific record from the application (2), the offset-added structure is requested from the output unit (1102) of the control unit (11) The extracted structured data (4) is extracted, and the extracted structured data with offset (4) is output to the application (2). Based on the offset information, the application (2) that acquired the data can access a specific data element at high speed, and attempts to realize high-speed access to the specific data element among the data stored in the database. It is an invention to do.
JP 2008-140310 A

However, not limited to the technique of Patent Document 1, generally, if an offset is stored for each data or record for each data or record, the data size increases accordingly and a large memory is required. In other words, the memory capacity decreases as the offset is eliminated.
However, if the offset of the preceding and following data and the offset of the preceding and following records are not stored, when trying to refer to specific data and records, each data and record must be counted in order from the top of the list of data and records. Not only that, but the response gets worse. For example, as in the example of the list in which the conventional data in FIG. 6B is stored, it returns to the first data as the base point every time and returns to the “XXXX” position at the data number 66, and the “YYYY” position at the data number 129. In the data number 193, it is necessary to repeatedly select specific data from the first data as the base point, as in the “ZZZ” position, and since the search is repeated from the first data, the response becomes worse.

  Accordingly, the present invention has been made to solve such a problem, and a data list read / write device that reduces memory capacity by minimizing offset stored in data and records and minimizes response degradation. And the provision of the method.

2. The data list read / write device according to claim 1, wherein each data is sequentially stored together with a data number sequentially assigned in correspondence with the number of data at a specific position without corresponding an offset to each of the plurality of data. The created data storage unit without offset and the data stored sequentially at a specific position of the data storage unit without offset are associated with the data number and the offset for each predetermined data interval, and the data stored without offset is stored. An offset table associated with a data section, and data without offset are sequentially written in the data storage section without offset together with a data number, and the data number and offset are associated with each other at a predetermined data number interval in the offset table. Write, data recovery of the data storage unit without offset When selecting the desired data from the bets, the select nearest offset from the offset table, and calculates the amount of movement of the data number between the data number which the offset is applied with the data number of the desired data, A reading / writing unit that specifies the position of the desired data based on the data number to which the offset is added and the movement amount is provided.
In general, a record means a unit of data, and there is a difference in the contents of the data, but each is only a difference between small data and large data, and both are data. In the present invention, both are used without distinction. Therefore, in the present invention, the description of data is interpreted as a synonym for a record, and only the data representation is used throughout the present invention.
Here, the offset-free data storage unit sequentially stores data obtained from a database in which a plurality of offsets are deleted at a specific storage position.
Further, the offset table associates offsets at predetermined equal intervals or at arbitrary intervals, such as every 25 data, every 50 data, every 100 data, etc., for each of a plurality of data stored sequentially. It is a table and is paired with the data storage unit without offset. The predetermined interval corresponding to the offset is not limited to those provided at equal intervals, such as every 25, every 50, every 100, etc., and may be a non-uniform interval or a specific interval. You may change the space | interval by more than a number and below a number. However, if an offset is assigned in the offset table and the predetermined data interval is set to an odd number and an offset is given, the numerical value between them becomes an even number, and it is determined whether the distance to arrive at the offset should be counted up or counted down Can be simplified. For example, if the last three digits of the data number are “001”, “051”, “101”, “151”,..., “951”, there are 50 memory numbers, and the last two digits are “25”. When the value is “Less than or equal to” or “Less than or equal to 75”, the countdown is performed.
When the read / write unit selects desired data from the specific data list stored in the data storage unit without offset, the nearest offset is selected from the offset table, and the desired data is stored based on the offset. Add or subtract the number of data and read the corresponding data. Of course, when the number of data stored in the data storage unit without offset is unknown, in order to select the nearest offset from the offset table, the data number is sequentially subtracted from the predetermined data number and the nearest offset is searched. .

  The predetermined data interval corresponding to the offset in the offset table of the data list read / write device according to claim 2 is an odd value such as every 50, every 100, every 200, etc., except for the first. , For example, 1, 51, 101,..., 901. In other words, the number of data during the data interval is an even number, and there is no intermediate data number between the upper data number and the lower data number corresponding to the offset, so it is necessary to process how to handle the intermediate value. Disappear.

  When the reading of a desired data number is instructed, the reading / writing unit of the data list reading / writing device according to claim 3 subtracts from the desired data number and searches for the data number to which the nearest offset is given. . Here, what performs only subtraction to the desired number of data should just have a countdown function.

  The calculation to the desired number of data based on the data number to which the offset is given in the read / write unit according to claim 4 is performed by adding or subtracting from the data number to which the nearest offset is given to the desired data number, The data number to which the offset is assigned is searched. Here, the addition or subtraction up to the desired number of data means that the nearest offset corresponding to the selected data number is efficiently selected, so the threshold value for addition or subtraction is the reference. is there.

The data list read / write method according to claim 5 stores the corresponding data together with the data numbers sequentially assigned in correspondence with the number of data at a specific position without corresponding the offset to each of the plurality of data, A step of creating a data list, and a step of associating the data number with an offset for each predetermined data number interval with respect to a data number stored at a specific position in the data storage unit without offset, the offset The data without offset is sequentially written in the no-data storage unit together with the data number, and the data number and the offset are written in correspondence to each predetermined data number interval in the offset table, and the data list of the no-offset data storage unit From the offset table when selecting desired data from Select the offset deviation, the data the amount of movement of the numbers calculated, the amount of movement data number which the offset is applied between the data number to which the offset is applied to the desired data number of the data Based on this, the position of the desired data is specified .

The data list read / write device according to claim 1 is a data list read / write device that reads a large number of stored data, sequentially writes desired data, and creates a specific readable data list. The offset data is sequentially stored in a specific position without corresponding to each of the plurality of data, and the offset data corresponding to the offset table linked with the offset-free data storage unit is correlated with the predetermined data interval, and the specific data list When selecting desired data from, select the nearest offset from the offset table , calculate the amount of movement of the data number between the data number to which the offset is given and the data number of the desired data, Based on the data number with the offset and the amount of movement It is to determine the location of the desired data Te.
Accordingly, since it is not necessary to associate an offset with each data, a memory area corresponding to the offset information can be omitted, and the memory capacity can be reduced. In addition, even when calculating the number of data up to the desired number of data based on a specific offset, because it does not count from the beginning of the data as a base point, the selection speed is not enough to make you aware of the response drop, The response is almost unrecognizable.

  Since the data list read / write device according to claim 2 corresponds to the offset in the offset table, the predetermined data interval is for each data number of the first data number and the predetermined odd interval. In addition to the effects described above, the number of data during the data interval is an even number, the number of intermediate data between the upper and lower data numbers corresponding to the offset is an even number, and there is no intermediate value as the boundary. Therefore, it is not necessary to perform the process of how to handle an intermediate value in which the distance between the upper data number and the lower data number is the same. The response gets better.

  Since the reading section of the data list read / write device according to claim 3 subtracts up to the data number to which the offset is assigned, in addition to the effect of claim 1 or claim 2, the data storage without offset is stored. Even if the total number of data stored in the section is unknown, it can be searched, and the response can be improved by a predetermined data interval corresponding to the offset in the offset table.

  The reading unit of the data list read / write device according to claim 4, wherein the calculation up to a desired number of data based on the data number to which the offset in the read / write unit is assigned is based on the data number to which the nearest offset is assigned. In addition to the effect described in any one of claims 1 to 3, in addition to the effect described in any one of claims 1 to 3, an offset is associated with the offset table and an even number of predetermined data intervals are added. With each setting, the processing speed of the microfilm processor is high, and the response is hardly recognizable.

The data list read / write method according to claim 5 is provided for an offset table that is sequentially stored in a specific position without causing an offset to correspond to each of a plurality of data in an offset-free data storage unit and linked to the offset-free data storage unit. When an offset is associated with a predetermined data interval and desired data is selected from the specific data list, the nearest offset is selected from the offset table, the data number to which the offset is assigned, and the desired data The movement amount of the data number between the data numbers is calculated, and the position of the desired data is specified based on the data number to which the offset is added and the movement amount.
Accordingly, since it is not necessary to associate an offset with each data, a memory area corresponding to the offset information can be omitted, and the memory capacity can be reduced. In addition, even when calculating the number of data up to the desired number of data based on a specific offset, because it does not count from the beginning of the data as a base point, the selection speed is not enough to make you aware of the response drop, It is possible to respond with a response that can hardly recognize a decrease in response.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that, in the embodiment, the same symbols and the same reference numerals in the drawings are the same or corresponding functional parts in the drawings, and thus redundant description is omitted here.

[Embodiment 1]
FIG. 1 is a block diagram showing an overall configuration in which the data list read / write device according to the first embodiment of the present invention is functionally expressed. FIG. 2 is a flowchart of writing of the data list read / write device according to the first embodiment of the present invention. 3 is a flowchart of reading by the data list read / write device according to the first exemplary embodiment of the present invention.

In FIG. 1, the data list read / write device according to the present embodiment is conceptually shown as a whole: database 1, application 2, display 3, input unit 4, offset-free data storage unit 5, offset table 6, read / write unit 7. The whole is configured as a microprocessor 10 to which a display 3 and an input unit 4 and various external devices 8 necessary for, for example, a navigation device are attached.
The database 1 is a collection of data shared by one or more application software, and the navigation device collects and manages map data and index data used for destination search, and easily searches and extracts various forms. It has been made available in. In general, a navigation apparatus holds such data so that an address, facility name, station name, postal code, spot name, genre, and the like can be searched.

The application 2 is a processing function including a computer program for data processing used for a specific application. In the navigation device, the application 2 is used as a destination setting address search function, a facility name search function, and the like.
The display 3 is a display means composed of liquid crystal for displaying operation information, information such as a map, information for writing map data, etc. to an operator. The input unit 4 is an operation from an operator such as a driver in a navigation device. Key input, voice input, touch switch, and the like for receiving the input. As the input unit 4, a keyboard, a mouse, a barcode reader, a remote control device for remote control, etc. may be used on the front of the display 3. It can also be configured with a touch panel.

The offset-free data storage unit 5 is a RAM that sequentially stores data together with data numbers at specific positions without corresponding offsets to a plurality of pieces of data, and creates a desired data list. Anything is possible. Usually, a memory in which a data number is assigned to each predetermined memory area and data can be stored is used.
The offset table 6 is a RAM that associates data numbers and offsets at predetermined data number intervals with respect to data sequentially stored in the data storage position of the specific data number of the data storage unit 5 without offset. The none data storage unit 5 and the offset table 6 can be formed by providing both areas in the same RAM.

  The read / write unit 7 outputs a signal for sequentially writing the data without offset to the data storage unit 5 without offset together with the data number, and writes the data number and offset to the offset table 6 at predetermined data number intervals. Write the data number and offset only for each number interval. When desired data is selected from the data list of the data storage unit 5 without offset, the nearest offset is selected from the offset table 6, and the desired number of data is added or subtracted based on the data number to which the offset is assigned. Then, the desired data is read out. That is, when reading data of a specific data number, first, the nearest data number with an offset is specified from the specific data number, and then the data number is sequentially increased from the data number with the offset. That is, the data number is counted up or the data number is sequentially decreased, that is, the data number is counted down, and a specific data number is read out.

The timing of the read / write unit 7 that writes data numbers and offsets at predetermined data number intervals in the offset table 6 is, for example, the last three digits are data numbers “001”, data numbers “051”, “101”, “151”, ..., If a data number and an offset are written in “951”, there are 50 memory numbers in between. At this time, as a threshold for determining addition or subtraction, when the last two digits are “X25 or less” or “X75 or less”, the countdown is performed, and when “X26 or more” or “X76 or more”, the countup is performed. Here, an integer from 0 to 9 is substituted for X. However, this addition or subtraction is applied below the maximum value of the data number having the offset written in the data storage unit 5 without offset. If the maximum value of the data number written in the data storage unit 5 without offset is unknown, the offset can be obtained only by counting down from the designated data number.

  In the case of an in-vehicle navigation device, the external device 8 required for the navigation device or the like can be variously detected so as to be able to detect the current position, orientation, distance to a target position (for example, an intersection), and the like. A current location detection unit that detects the current location of the vehicle including sensors, and a map information processing unit consisting of a hard disk with a large storage capacity in which various types of map data are recorded, written and read, and a predetermined distance range from the destination A parking lot search unit for searching for a parking lot is provided.

Next, the operation of the data list read / write device according to the present embodiment will be described using the flowcharts of FIGS.
The flowchart of FIG. 2 is a program that is called during execution of another main program. This program is used when the application 2 creates a list specified for its use. It can also be used as a display memory for displaying all data on the display 3.
When the application 2 that searches the destination by the name of the in-vehicle navigation that guides the vehicle to the destination in step S1 retrieves the data for creating the list specified by the destination search from the database 1, the data is stored in step S2. The data is extracted, assigned a specific data number, and stored in a specific memory, that is, the data storage unit 5 without offset. In step S3, it is determined whether the data number stored in the data storage unit 5 without offset is the number of data in the specified interval. For example, the data interval is set to every 50, every 100, or every 200. If it is, it is determined whether or not it is the first data number, the first data number, etc., and if the predetermined number of data (data number) is not reached, the presence of the search data is determined in step S5. Confirm and repeat step S2 to step S5. As a result, the data is sequentially stored in the data storage unit 5 without offset together with the data number.

  When the data number stored in the data storage unit 5 without offset in step S3 is the specified number of data, for example, 1, 51, 101, 151, 201,..., In step S4 The offset is written in the offset table 6 together with the data number. In step S5, the presence of the search data is confirmed. When the search data exists, steps S2 to S5 are repeatedly executed. When it is confirmed in step S5 that no search data exists, the writing of all data in the list to the data storage unit 5 without offset is completed in step S6.

The flowchart of FIG. 3 is also a program that is called during execution of another main program. This program is used when selecting predetermined data from all data displayed from the data storage unit 5 without offset.
When an instruction to read data of a specific data number is received by the input unit 4 from the predetermined list displayed on the display 3 in step S11, the nearest data number that is smaller than that is determined based on the specific data number in step S12. The data number with the offset is retrieved, the data number with the offset is read in step S13, the movement amount of the data number between the data number specified in step S11 is calculated in step S14, and the data number is calculated in step S15. To specify the data position. In step S16, predetermined data is read from the data number, stored, and used as display output on the display 3 as necessary.

[Embodiment 2]
In the display of the first embodiment, the case where it can be used as the display memory of the display 3 has been described. However, when the present invention is implemented, the response can be improved.
FIG. 4 is a flowchart of writing of the data list read / write device according to the second embodiment of the present invention, and FIG. 5 is a flowchart of reading of the data list read / write device according to the second embodiment of the present invention.

The flowchart of FIG. 4 is a program that is called during execution of another main program. This program is used when the application 2 creates a list specified for its use. It can also be used as a display memory for displaying all data on the display 3.
First, when data for creating a list specified for its use is retrieved from the database 1 by the application 2 in step S21, the number of data is counted and the number of data N is specified in step S22. In step S23, specific data out of the number N of data is extracted, assigned a specific data number, and stored in the data storage unit 5 without offset. In step S24, it is determined whether the data number stored in the data storage unit 5 without offset is the specified number of data. For example, if the data interval is every 50, the first first , 51,..., Etc., and if the number is not the predetermined number of data (data number), the number is incremented by “−1” in step S26, and the number of data is determined in step S27. Whether N is not zero or the presence of the search data is confirmed. When the number of data N is not zero, the routine from step S23 to step S27 is repeatedly executed. As a result, the data is sequentially stored in the data storage unit 5 without offset together with the data number.

  When the data number stored in the data storage unit 5 without offset in step S24 is, for example, 1, 51, 101, 151, 201,... In step S25, the offset is written in the offset table 6 together with the data number. In step S27, the presence of the search data is confirmed. When the search data exists, steps S23 to S27 are repeatedly executed. When it is confirmed in step S27 that the search data does not exist, in step S28, writing of all data in the list to the data storage unit 5 without offset is completed.

The flowchart of FIG. 5 is also a program that is called during execution of another main program. This program is used when selecting predetermined data from all data displayed from the data storage unit 5 without offset.
When an instruction to read data of a specific data number is received from the predetermined list displayed on the display 3 in step S31, the data number specified in step S32 is equal to or less than the total number N of data written. If the total number of data is not less than N, it is waited for correction. If the total number of data is less than N, it is determined in step S33 whether the number of the designated data number is equal to or greater than a predetermined threshold position. That is, when the data interval is every 50, the data number and offset are recorded in the offset table 6 with data number 1, data number 51, data number 101, data number 151, data number 201,. At this time, when the last two digits are “X25 or less” or “X75 or less”, it is shorter to count down and select the previous offset. However, when “X26 or more” or “X76 or more”, it is shorter to count up and select a later offset. Therefore, a better response is selected in step S33.

  Further, in step S34, it is determined from the nearest offset corresponding to the maximum data number whether the value is a number less than that with reference to the maximum data number having the offset. That is, in the case of the maximum data number, the data number is reached only by counting down to reach the data number having an offset, so that the maximum of the data number corresponding to the data number and the offset is obtained or less, It is determined whether or not, and subsequent count up or count down processing is performed.

In step S33 or step S34, the last two digits are “X26 or more” or “X76 or more”.
When the data number is equal to or greater than the threshold value or when the data number and the offset are less than the maximum corresponding data number, the number of the data number is counted up in step S35, and the counted up value is stored in step S36, and step S37 is stored. It is determined whether or not the data number with the offset has been reached, and the routine processing from step S35 to step S37 is continued until the data number with the offset is reached.

In step S33 or step S34, the last two digits are "X25 or less" or "X75 or less"
If the data number and the offset exceed the maximum corresponding data number, the number of the data number is counted down in step S38, and the value counted down in step S39 is stored, and in step S40. It is determined whether or not the data number with the offset has been reached, and the routine processing from step S38 to step S40 is continued until the data number with the offset is reached.

  When the data number with the offset is reached in step S37 or step S40, the data number corresponding to the offset and the data number is read in step S41, and the data between the data number specified in step S31 is read in step S42. The movement amount of the number is calculated, and the data position is specified from the data number in step S43. In step S44, predetermined data is read from the data number, stored, and displayed on the display 3 as necessary.

  The data list read / write device of the above embodiment is a data list read / write device that reads a large number of stored data, sequentially writes desired data, and creates a readable data list from the written data. The data corresponding to the data number and the corresponding data number are stored in the specific position without corresponding the offset to each data, and the non-offset data storage unit 5 for creating a desired data list and the specific position of the non-offset data storage unit 5 An offset table 6 that associates the data number with an offset for each predetermined data number interval with respect to the stored data number, and data without offset are sequentially written in the non-offset data storage unit together with the data number. , And the data number for each predetermined data number interval When the offset is written to the offset table 6 and desired data is selected from the data list of the data storage unit 5 without offset, the nearest offset is selected from the offset table 6 and the data number to which the offset is assigned is selected. Includes a read / write unit 7 that calculates up to the desired number of data. In addition, predetermined data is displayed on the display 3 as necessary.

Here, the non-offset data storage unit 5 of the first embodiment functions as step S1 to step S3 and step S5, and data corresponding to a specific position together with a data number without making an offset correspond to each of a plurality of data. And a desired data list is created.
Moreover, the offset table 6 of Embodiment 1 acts as step S3 and step S4, and with respect to the data number stored in the specific position of the data storage unit 5 without offset, It has the structure which makes an offset correspond.

  The read / write unit 7 according to the first embodiment functions as Steps S1 to S6 and Steps S11 to S16, and sequentially writes data without an offset together with a data number into the data unit 5 without offset. When the data number is written in the offset table 6 in correspondence with the data number interval and the desired data is selected from the data list of the data storage unit 5 without offset, the nearest offset is selected from the offset table 6 A desired number of data is calculated based on the data number to which the offset is assigned.

Similarly, the offset-free data storage unit 5 of the second embodiment functions as step S21 to step S24, step S26, and step S27, and includes a data number at a specific position without corresponding an offset to each of a plurality of pieces of data. It has a configuration for storing corresponding data and creating a desired data list.
Further, the offset table 6 of the second embodiment acts as step S24 and step S25, and with respect to the data number stored in the specific position of the data storage unit 5 without offset, It has the structure which makes an offset correspond.

  The read / write unit 7 according to the second embodiment functions as Steps S21 to S28 and Steps S31 to S44, and sequentially writes data without an offset together with a data number to the data unit 5 without offset. When the data number is written in the offset table 6 in correspondence with the data number interval and the desired data is selected from the data list of the data storage unit 5 without offset, the nearest offset is selected from the offset table 6 A desired number of data is calculated based on the data number to which the offset is assigned.

As described above, in the first and second embodiments, a large number of data stored in accordance with the application 2 is read, desired data is sequentially written, and a specific data list that can be read is created. In the list read / write device, a plurality of data is sequentially stored in a specific position in the non-offset data storage unit 5 without corresponding an offset, and is offset at a predetermined data interval with respect to the offset table 6 linked to the non-offset data storage unit 5 When the desired data is selected from the specific data list, the nearest offset is selected from the offset table 6, the number of data is calculated up to the desired number of data based on the offset, and the desired data is read from the read / write unit 7. Data can be read out.
Accordingly, since it is not necessary to associate an offset with each data, a memory area corresponding to the offset information can be omitted, and the memory capacity can be reduced. In addition, even when calculating the number of data up to the desired number of data based on a specific offset, because it does not count from the beginning of the data as a base point, the selection speed is not enough to make you aware of the response drop, The response is almost unrecognizable and has no sense of incongruity.

  The data list read / write device according to the first embodiment and the second embodiment reads a large number of data stored in the database 1, sequentially writes desired data, and creates a readable data list. , Storing the corresponding data together with the data number in a specific position of the offset-free data storage unit 5 without making an offset correspond to each of the plurality of data, and creating a desired data list, and storing the data without offset An offset table 6 different from the non-offset data storage unit 5 is formed for the data number stored at a specific position of the unit 5, and the offset number 6 corresponds to the data number and the offset for each predetermined data number interval. And offsetting the data storage unit 5 without the previous offset. The data is sequentially written together with the data number, and the data number is written in the offset table 6 in correspondence with each data number interval, and desired data is selected from the data list of the data storage unit 5 without offset. In this case, the nearest offset is selected from the offset table 6, and the embodiment of the invention of the data list read / write method for calculating the desired number of data based on the data number to which the offset is assigned can be used.

As in the second embodiment, the intervals of the predetermined data numbers corresponding to the offsets in the offset table 6 are, for example, the last three digits of the data numbers “001”, “051”, “101”, “151”. ,..., “951”, for each data number at the first data number and predetermined odd intervals.
Therefore, in particular, as in steps S33 to S40, the offset is associated with the offset table 6 and the predetermined data interval is for each data number of the first data number and the predetermined odd interval. The number of data in between is even, the number of data in the middle between the number of data on the upper side and the number of data on the lower side corresponding to the offset is an even number, and there is no intermediate value at the boundary. There is no need to process how to handle an intermediate value that is the same distance from the number of data as the response, and the response is improved accordingly.

As in the first embodiment, when the reading of a desired data number is instructed, the read / write unit 7 subtracts the desired data number and searches for the data number to which the nearest offset is given.
In this type of embodiment, even if the total number of data stored in the no-offset data storage unit 5 is unknown, it can be searched, and the response can be obtained by narrowing the predetermined data interval corresponding to the offset in the offset table 6. Can do well.

  As in the second embodiment, the calculation to the desired number of data based on the data number to which the offset is given in the read / write unit 7 is added from the desired data number based on the data number to which the nearest offset is given. Or, since it is to subtract, in the offset table 6 that corresponds to the offset and set the even number of predetermined data intervals, the processing speed of the microfilm processor is fast, not to the extent that the response reduction is conscious, Good response almost unrecognizable.

  The offset-free data storage unit 5 and the offset table 6 in the above embodiment may be implemented as an area for storing data numbers and data in the same area and storing offsets at predetermined data number intervals. it can. That is, in the data storage unit 5 with no offset and the offset table 6 when the present invention is implemented, data numbers can be expressed in duplicate.

  Although the data list read / write device according to the first embodiment and the second embodiment has been described in the case where a specific list is created and read out, the list is an object of the navigation device when the present invention is implemented. It can be used as a display memory that is directly displayed on the display 3 to specify the ground.

FIG. 1 is a block diagram showing an overall configuration in which the data list read / write device according to the first embodiment of the present invention is functionally expressed. FIG. 2 is a flowchart of writing in the data list read / write device according to the first exemplary embodiment of the present invention. FIG. 3 is a read flowchart of the data list read / write device according to the first exemplary embodiment of the present invention. FIG. 4 is a flowchart of writing in the data list read / write device according to the second exemplary embodiment of the present invention. FIG. 5 is a read flowchart of the data list read / write device according to the second exemplary embodiment of the present invention. FIG. 6A is a conceptual diagram of a list example in which conventional data is stored, and FIG. 6B is a conceptual diagram of a modified example of a list in which conventional data is stored.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Database 2 Application 3 Display 4 Input part 5 Data storage part without offset 6 Offset table 7 Reading / writing part

Claims (5)

In a data list read / write device that reads a large number of data stored in a database, sequentially writes desired data, and creates a readable data list,
An offset-free data storage unit for creating a desired data list by storing corresponding data together with data numbers sequentially assigned in correspondence with the number of data at specific positions without corresponding offsets to a plurality of pieces of data ,
An offset table in which the data number and the offset are associated with each other for each predetermined data number interval, with respect to the data number stored at a specific position of the data storage unit without offset,
The data without offset is sequentially written in the non-offset data storage unit together with the data number, and the data number and the offset are written in correspondence with each predetermined data number interval in the offset table. When selecting desired data from the data list, select the nearest offset from the offset table, and calculate the amount of movement of the data number between the data number to which the offset is assigned and the data number of the desired data. A data list read / write device comprising: a read / write unit that specifies a position of the desired data based on the data number to which the offset is added and the movement amount .  2. The data list read / write device according to claim 1, wherein an interval between predetermined data numbers corresponding to an offset in the offset table is set to each first data number and predetermined odd number data numbers.  The read / write unit, when instructed to read out a desired data number, subtracts from the desired data number and searches for the data number to which the nearest offset is assigned. Data list reading and writing device described.  The calculation up to a desired number of data based on a data number to which an offset is given in the read / write unit is characterized by adding or subtracting from a desired data number based on the data number to which the nearest offset is given. The data list read / write device according to any one of claims 1 to 3. In a data list read / write method for reading a large number of data stored in a database, sequentially writing desired data, and creating a readable data list,
Storing a corresponding data together with a data number sequentially assigned in correspondence with the number of data at a specific position without corresponding an offset to each of a plurality of data, and creating a desired data list;
Correlating the data number with an offset for each predetermined data number interval , with respect to the data number stored at a specific position in the data storage unit without offset,
The data without offset is sequentially written in the non-offset data storage unit together with the data number, and the data number and the offset are written in correspondence with each predetermined data number interval in the offset table. When selecting desired data from the data list, select the nearest offset from the offset table, and calculate the amount of movement of the data number between the data number to which the offset is assigned and the data number of the desired data. A data list read / write method, wherein the position of the desired data is specified based on the data number to which the offset is added and the movement amount .

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