Data processing: database and file management or data structures – Database design – Data structure types
Reexamination Certificate
1998-11-10
2001-09-11
Choules, Jack (Department: 2177)
Data processing: database and file management or data structures
Database design
Data structure types
C707S793000, C707S793000
Reexamination Certificate
active
06289359
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is related to an improvement of a file managing method for a data file, which is directed to a process operation so that only necessary data is effectively derived from a large amount of saved data such as a database.
2. Description of the Related Art
Generally speaking, within a disk apparatus, data are grouped in units of a record, these data are arranged in accordance with a sequential order of the respective records, and the data are arranged in accordance with a definition order of fields within each of the records.
In
FIG. 24
, there is shown one example of the conventional file managing method in the file management. This drawing illustratively shows such a storage condition that records of a data file to be stored, which are defined from an i-th record up to “n” records have been stored in the disk apparatus.
Japanese Unexamined Patent Application No. Hei 6-176074, laid open in 1994 describes the technical aspect of the related database process operation. In this database process operation, after all of the data are once entered from the disk apparatus into the input/output buffer employed in the database calculating process apparatus, only necessary data are acquired into the internal memory by way of the selecting process operation and the projecting process operation. This technique is intended to effectively utilize the internal memory. However, no detailed explanation is given of the data definition by executing the selecting process operation and the projecting process operation. Also, no description is given of the method for utilizing the data acquired in the internal memory.
In such an above-described storage format in which the data are grouped in the units of the record and the grouped data are stored, even when only a partial field contained in the record is required, all of the records are inputted from the disk apparatus to the input/output buffer, and thereafter a process operation for separating only the necessary records is required.
A process operation for deriving only a partial field corresponds to such a process operation for deriving, for instance, only a name and an address from a staff member database constituted by numbers of staff members, names, ages, addresses, and telephone numbers. As shown in
FIG. 25
, while a field
17
corresponds to the names and another field
18
corresponds to the addresses, even when only two fields are required, since the data are not stored in the disk apparatus in such a manner that these data are subdivided by every field, all of the fields must be read out from the disk apparatus as to all of the records. Then, the process operation for separating the field
17
and the field
18
must be carried out.
Since the conventional file managing method is arranged in the above-described manner, even when only a partial field contained in the records is needed, all of the records must be entered from the disk apparatus into the input/output buffer. There is a problem. That is, even when the file is formed by separating only the necessary field, since the necessary fields are different, depending upon the use of the file, a process operation for separating only the necessary field must be carried out every time the file is used.
SUMMARY OF THE INVENTION
The present invention has been made to solve the above-described problem, and therefore, has an object of providing a file managing method. That is, since only a portion containing a field required in a process operation is read out from a disk apparatus and an amount of data read from the disk apparatus is reduced, the time required to read the data from the disk apparatus is shortened and thus the high speed operation can be realized.
A file managing method, according to the present invention, is featured by that a preselected number of records are subdivided from an original file for storing thereinto a plurality of records constituted by a plurality of fields so as to set the subdivided fields as blocks; all of these subdivided blocks are coupled to each other so as to rearrange these subdivided blocks as a group; as to all of the plural records, the respective subdivided blocks thereof are rearranged as the groups, and thereafter these rearranged groups are coupled to each other so as to produce a transposed file; and the fields are accessed at random from the transposed file.
Also, the file managing method is featured by that each of the fields of the record is changed into either one or a plurality of fields having fixed lengths every field; and after all of the records are changed into fields having fixed lengths, the fixed-length-fields are subdivided from the original file so as to set the subdivided fields as blocks.
Further, the file managing method is featured by that either one or plural fields of the record, which are located adjacent to each other, are combined with each other to be changed into a field having a fixed length.
Also, the file managing method is featured by that after the fields are sequentially formed by a fixed value from a head position of the record to thereby form an entire area of the records as a field having a fixed length, the field having the fixed length is subdivided from the original file so as to form a block.
Further, the file managing method is featured by that the order of records within the block is changed every block.
Further, the file managing method is featured by that a record starting position within the block is changed every block, and the records within the block are arranged by way of a wrap around manner.
Also, the file managing method is featured by that the coupling sequence of the blocks within the group is changed every group.
Further, the file managing method is featured by that blocks which have high possibilities to be accessed simultaneously are arranged adjacent to each other.
Also, the file managing method is featured by that a preselected number of records selected from an original file for storing therein a plurality of records constituted by a plurality of fields are subdivided from the original file so as to set the subdivided fields as blocks; all of the subdivided blocks are coupled to each other to rearrange the subdivided blocks as groups; the groups are stored into a plurality of disk apparatuses every a preselected number of the groups; and the respective disk apparatuses are accessed in a parallel manner as to an access operation to the original file.
Further, the file managing method is featured by that either a maximum value or a minimum value of the field values of the records is acquired every the group to retrieve the records.
Also, the file managing method is featured by that an identifier indicative of either an entering order of the records or entering timing of the records is added to the record; and either a maximum value of the identifier or a minimum value of the identifier is acquired with respect to each of the groups to thereby retrieve the record.
REFERENCES:
patent: 5247665 (1993-09-01), Matsuda et al.
patent: 5327341 (1994-07-01), Whalen et al.
patent: 5577242 (1996-11-01), Yamaguchi et al.
patent: 5628007 (1997-05-01), Nevarez
patent: 5991753 (1999-11-01), Wilde
patent: 6176074 (1994-06-01), None
“Sybase IQ”, Jun. 17, 1998.
“Oracle 7 Server Distributed Systems vol. II: Replicated Data”, Jun. 20, 1998.
Ando Takaaki
Hayakawa Takayuki
Kori Mitsunori
Michishita Manabu
Yoshimura Keiji
Choules Jack
Lewis Cheryl
Mitsubishi Denki & Kabushiki Kaisha
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