JPH04318673A - Split indexing/retrieving system - Google Patents

Abstract

PURPOSE:To provide an index sequential access method in a record split storage system for data base. CONSTITUTION:To records that are splitted in a certain unit of storage in accordance with a record split rule, a keyword analysing means 1 for extracting a specified condition from an application program, a range information extracting means 2 for reading specified definition information, a range unit retrieving means 3 for executing retrieval for each unit of storage, a bit map connecting means 4 for carrying out inspection of storage unit, and a retrieval instruction executing means 5 for retrieving the optimum record are applied to obtain an object record, thereby being able to access records in unit of table or unit of storage in order of index in a split storage system.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to control of the division method of a database file management system in an electronic computer system.

0002

2. Description of the Related Art In the conventional divided storage method, the storage unit is determined for the value of a certain item in a record, and the storage unit for an index is also determined based on the value of that item. Thereby, index-order processing is closed within the storage unit.

In the conventional method described above, index order processing is performed by specifying a storage unit in which records are stored, and the search order is the index order within the storage unit. A drawback is that index-order processing is not possible throughout the table or within a particular storage unit, regardless of the values of the items that are partitioned into storage units.

[0004] In the conventional method, in order to process the entire table in index order, the application program must execute a search command for each storage unit and compare each record in the search results to extract the desired record. Otherwise, the processing becomes complicated.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an index order access method using a record division storage method in a database.

[0006]

[Means for Solving the Problems] According to the present invention, a set of records having a specific record format is expressed as a table, one or more items are combined and expressed as an index, and a certain In a file management system that divides and stores records into multiple storage units according to the rules of range information collection means for reading from the device; range unit search means for searching the storage unit determined by the keyword analysis means; and bitmap combination for inspecting the storage unit from the information obtained by the range information collection means. and search command execution means for searching the bitmap combination means for an optimal record required by an application program.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings.

In this embodiment, the record storage unit is expressed as a range.

Referring to FIG. 1, one embodiment of the present invention includes keyword analysis means 1, range information collection means 2, range unit search means 3, bitmap combination means 4, search command execution means 5, It consists of a definition information storage device 6, a work area 7, and a database file group 8. Figure 2
1 is a detailed flow of processing performed by the keyword analysis means 1 and the table information collection means 2.

FIG. 3 shows the detailed processing flow of the range unit search means 3, the bitmap combination means 4, and the search command execution means 5.

First, explanation will be given using FIG. 2.

The keyword analysis means 1 reads the table information record 22 from the definition information storage device 6 when the application program 21 is activated and a table is opened. Next time the search command is executed, the parameters are analyzed and the RANGE
Checks if is specified. If the RANGE parameter is specified, the specified range number is retrieved, the range information collection means 2 is activated, and the process ends.

The range information collecting means 2 first reads the range division information record 23 of the open table from the table information record of the table from the definition information storage device 6. If the table is not range-divided, the process ends regardless of the presence or absence of the RANGE parameter. The table is divided into ranges,
Further, when the range number is collected by the keyword analysis means 1, the range number obtained by the keyword analysis means is read from the record storage range number 24 of the range division information record 23. If the range number is undefined or prohibited from use, the process is stopped. If the range number is defined and available, the index range number 25 corresponding to the specified range number is set to index range number 2 of the range index information record 26.
7 and collect the next range number. When all range tests are completed, the target index range number is input into the range number section 28, and the range unit search means 3 is activated. If "ALL" is specified as the range number, all range numbers and range numbers of the specified index are input into the range index information record 26. At that time, if there are records or index storage ranges that are prohibited from use, they are removed. If the table is divided into ranges and the RANGE parameter is not specified, the operation is performed as if "ALL" was specified as the range number. After inputting each piece of information, the range unit search means 3 is activated to complete the process.

Next, explanation will be made using FIG. 3.

The range unit search means 3 reads out the address number of the record of the specified value from the first index range 27 of the range index information record 26 in bitmap format. From the address number, the keyword analysis means 1 searches for a record stored in a range that has not been collected, and if a corresponding record is found, the address number of the index is turned OFF on the bitmap record 31. After all address numbers on the bitmap have been checked, the number of ranges 28 in the range index information record 26 is counted down. When the number of ranges becomes 0, the search command execution means 5 is activated, and otherwise the bitmap combination means 4 is activated.

Similar to the range unit search means 3, the bitmap combining means 4 creates a bitmap record 31 of the specified value from the next index range, checks the range number, and creates the target bitmap. The range unit search means 3 combines the bitmap created immediately before. Furthermore, when the next index range is processed and all index ranges are completed, the index command search means 5 is activated and the processing is completed.

The search command execution means 5 obtains a target record from the bitmap obtained by the previous means by executing a conventional search command.

[0018]

Effects of the Invention As explained above, the present invention allows processing of index order within a specified area by specifying a storage unit number from a program with an index search command in a divided storage system. It makes it possible. According to the present invention, it is possible to search through a storage unit or the entire table, and while taking advantage of the characteristics of the divided storage method, a wide variety of access routes are guaranteed.

[Brief explanation of drawings]

[Fig. 1] A diagram showing an embodiment of the present invention.

[Figure 2] Flowchart of processing of index split search method

[Figure 3] Flowchart of processing of index split search method

[Explanation of symbols]

1 Keyword analysis means 2 Range information collection means 3 Range unit search means 4 Bitmap combination means 5 Search command execution means 6 Definition information storage device 7 Work area 8 Database file group 21 Application program 22 Table information record 23 Range division information record 24 Record range number 25 Index range number 26 Range index information record 27 Index range number 28 Number of ranges 31 Bitmap record

Claims (1)

[Claims] [Claim 1] A set of records with a specific record format is expressed as a table, one or more items are combined and expressed as an index, and the records are divided into multiple storage units according to a specific rule. In a file management system that divides and stores and holds the file, the keyword analysis means analyzes instructions specified by an application program, the range information collection means reads range definition information specified by the application program from a definition information storage device, A range unit search means for searching the storage unit determined by the keyword analysis means, a bitmap combination means for examining the storage unit from the information obtained by the range information collection means, and from the bitmap combination means. A split index search method comprising a search command execution means for searching for an optimal record required by an application program.