JPH06295313A - Data retrieving device for retrieving file with index - Google Patents

Abstract

PURPOSE:To provide index-added retrieving file data retrieving device capable of retrieving specific field data without accessing data up to a record part. CONSTITUTION:An index-added retrieving file index part is provided with a field data storing area 35 for storing prescribed field data such as field data to be frequently used for data retrieval. In the case of requiring only the data stored in the area 35, only the index part in this data retrieving device is accessed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvement of search means in a data search device for a search file with an index.

[0002]

2. Description of the Related Art Among data files, there is an indexed search file having an index portion for facilitating the search for a record consisting of fields of a plurality of items.
In such an indexed search file, the index key, which is the key data of the record, is stored in the index portion. In the search method that uses such a data file to search for the required record from the multiple records stored in the data file using the index part, first specify the key data of the record you want to search The device retrieves the index key corresponding to this key data. The data retrieval device
When the index part is accessed and an index including the corresponding index key is found, the record indicated by the index is read out. The data search device performs processing such as displaying the data of the read record on the display unit.

[0003]

However, when performing a data search, it may not be necessary to use all the data stored in a record. In that case, the data stored in a field that is rarely used is stored. Even the data will be read out. Normally, the record part exists on the hard disk, so in such a case, extra hard disk access processing is performed, the overall processing speed becomes slower, and if the record part is long, that much There was a problem that a read buffer was needed.

An object of the present invention is to provide a data search device for a search file with an index, which solves the above-mentioned drawbacks by storing in the index section the data stored in the fields that are frequently used when performing data search. To do.

[0005]

A data search apparatus for a search file with an index according to the present invention includes a record section for storing a plurality of records including fields of a plurality of items, an index key for searching the records, and an inside of the record. A search file composed of an index section for storing predetermined field data, and when searching the predetermined field data, only the index section is accessed, and when searching for the record, the index section and the It is characterized in that a search means for accessing both record parts is provided.

[0006]

In the data search device for the indexed search file of the present invention, since the index file structure in which the index key for searching the record and the predetermined field data in the record are also arranged in the index part, The data retrieval device
When searching the predetermined field data, it is sufficient to access only the index section. That is, it is not necessary to access the record part thereafter. On the other hand, when searching the record, that is, when it is desired to use field data other than the predetermined field data, the data search device accesses both the index section and the record section. Therefore, by using the predetermined field data as frequently used field data, the search processing time of the entire search device is shortened.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram showing the structure of a record stored in a record section of a data search device for an indexed search file according to an embodiment of the present invention. This indexed search file is a negative file used to check if your credit card is valid. The record 6 stores a field 1 for storing the invalid number at the beginning of the invalid card, a field 2 for storing the invalid range, a field 3 for storing the invalid year and month, a field 4 for storing the invalid reason code, and a invalid reason. And a field 5 to do so. In this file,
When the invalidation date, the invalidation reason code, and the invalidation reason are the same and the numbers of the invalidated credit cards are consecutive, these are stored in one record by the field shown in FIG. The leading invalid number indicates the leading number of consecutive invalid credit cards. If there are no consecutive invalid credit cards, the leading invalid number is the number of the single invalid credit card. The invalid range indicates a range of invalid credit card numbers following the invalid start number. The invalidation date is data of the invalidation date. The invalidation reason code is a code indicating the reason why the credit card is invalid. The invalidation reason is the content of the invalidation reason code indicated by characters. The record shown in Figure 1 shows that three credit cards with credit card numbers 500, 501, and 502 were invalidated in February 1992 due to loss. Note that the card number is actually a longer number of digits, but is shown here as a three-digit number for easier understanding. In this way, when credit cards with consecutive numbers become invalid at the same time and for the same reason, by storing these as one record, the amount of data stored in the file memory can be reduced. .

FIG. 2 is a diagram showing an example of the structure of hierarchical indexes. Now, the number of records in the data section is 100
Assume 0. The hierarchized index has a single highest index 11. Ten lower indexes 12 of the next layer are connected to the highest index 11, and each index is classified into 100 index keys. Further, each of the 10 lower indexes 12 is also connected to a plurality of indexes in the next layer. In this way, the indexes of the next layer are connected to each index, and the uppermost index 11 to the plurality of lowest indexes 13 which are the indexes of the lowest layer are connected in a tree structure. In the present embodiment, the lowest index 1
Each index of 3 stores 10 index keys. Here, the index of the next lower hierarchy connected in the tree structure is called a link index. However,
In the data search device, since each index is not stored in such a form and all the indexes are stored sequentially, an index is attached to each index and an index that is connected to a lower index to an upper index. The tree structure is realized by storing the label of.

FIG. 3 is a diagram showing the data structure of the index part according to the embodiment of the present invention. The indexes 11 and 12 other than the lowest index 13 are provided with an index level storage area 21, a search index information storage area 22, a key data storage area 23, and a link index No storage area 24 (FIG. Three
(See (A)). The lowest index 13 includes an index level storage area 31, an index information storage area 32 at the time of retrieval, and a key data storage area 33.
And a link data No storage area 34 and a field data storage area 35 that is frequently confirmed in the record (see FIG. 3B).

Index level storage areas 21, 31
Stores a flag for determining whether the index is the lowest index, 0 is stored in the lowest index 13, and 1 is stored in the other indexes 11 and 12. The index information storage areas 22 and 32 at the time of search store data such as the label of the adjacent index in the same layer, the label of the index in the next upper layer connected in a tree shape, and the number of link indexes. . This is used when adding or deleting a record. For indexes other than the lowest index 13, index keys (key data) of a plurality of link indexes are stored in the key data storage area 23, and labels of these link indexes are stored in the link index No storage area 24. For example, in the highest index 11 of FIG. 2, (1 to 100), (101 to 2) are stored in the key data storage area 23.
00) ... The key data of (901 to 1000) are stored in the link index No storage area 24.
The label of the link index (lower index 12 of the second layer) corresponding to each key data is stored. It should be noted that, in actuality, as the key data, the first one of the data that the link index is responsible for is used. That is, (1-100) is "1", (101-200)
To "101", ... (901 to 1000) to "90
1 ”is stored in the key data storage area 23. The key data storage area 23 and the link index No storage area 24 are stored as corresponding pairs. On the other hand, the lowest index Thirteen
Stores the key data (start invalid number) of all the records 6 connected to the key data storage area 33, and the link data No storage area 34 stores the address indicating the position where the record 6 is stored. Has been done,
Further, the field data storage area 35 stores field data (invalid range data) frequently confirmed in the record 6. This key data storage area 3
3, the link index No storage area 34, and the field data storage area 35 are stored as corresponding sets.

FIG. 4 is a diagram showing an operation flow of the data search apparatus. When the number of the credit card for which a negative check is desired is entered, the data search device will
1), using this as search data, the highest index 11
Start searching for. The data storage device detects the largest key data below the search data among the plurality of key data stored in the highest index 11 for the search data (n2).

Then, the data retrieval device reads the label stored in the link index No storage area 24 which is stored in pair with the detected key data (n3). The data search device shifts the search operation to the lower index 12 located at the position indicated by this label (n4). As a result, the index to be searched has moved to the next lower layer.

The data search device confirms the index level of the migrated index (n5). When the index level is 1, the data search device searches for this index in the same manner as the search for the highest index (n1 → 4). By repeating this, the data search device reaches the lowest index whose index level is 0.

The data search device detects the largest key data below the search data among the plurality of key data stored in the lowest index (n6). The data storage device reads the invalid range data stored in the field data storage area 35 paired with this key data (n7). Then, the data search device calculates the comparison data from the reached key data of the lowest index and the invalid range data (n8). This calculation is
The following formula is used.

Comparison data = index key data + invalid range data-1 For example, the content of the key data storage area detected by the lowest index 13 is 500, and the invalid range data stored as a pair is If it is 3, that is, the record shown in FIG. 1 is designated, the comparison data = 502.

Then, the data retrieval device compares the designated key data with the comparison data (n9), and when the designated key data ≦ comparison data, the credit card with the designated number is invalid. (N10). For example, if the designated key data is 500, 501, 502, it is determined that the credit card is invalid.

On the other hand, when the designated key data> comparison data, the data retrieval device determines that the credit card with the designated number is valid (n11). For example, if the designated key data is 503, it is determined that the credit card is valid.

Thus, the data retrieval device can perform a negative check of validity / invalidity of the credit card without accessing the data stored in the record.

Further, when it is necessary to access the record, the data search device uses the lowest index 13
The contents of this record can be read out by accessing the address shown in the link data No storage area 34, which is stored in combination with the key data storage area 33 detected in.

[0020]

As described above, according to the present invention, the data search device for the indexed search file stores the data of the field stored in the frequently confirmed record in the index section, and Only the index part can be accessed for data processing. As a result, the data processing can be performed without accessing the record, so that the processing time can be shortened.

[Brief description of drawings]

FIG. 1 shows a structure of a record stored in a record section of a data search device according to an embodiment of the present invention.

FIG. 2 shows a structure of hierarchical indexes.

FIG. 3 shows a data structure of an index of the data search device according to the embodiment.

FIG. 4 shows a negative check operation flow of the data search device according to the embodiment.

[Explanation of symbols]

 1, 2, 3, 4, 5, 5-Field 6-Record 11-Highest Index 12-Lower Index 13-Lowest Index

Claims (1)

[Claims] 1. A search comprising a record section for storing a plurality of records each including a field of a plurality of items, and an index section for storing an index key for searching the record and predetermined field data in the record. An index characterized by providing a file and search means for accessing only the index part when searching for the predetermined field data and accessing both the index part and the record part when searching for the record Data retrieval device for attached search files.