JPH03164839A - Data storage system - Google Patents

Abstract

PURPOSE:To shorten the time required to determine a block area where data can be stored by referring to area management information stored in an area management information storage means to detect a block including a usable storage area out of blocks of a data storage means and referring to block management storage information to store data in this block. CONSTITUTION:Area management information S1 to S32 indicating total capacities of reusable storage areas and unused storage areas in respective blocks are stored in an area management information storage means 122. Therefore, these area management information S1 to S32 are referred to detect a block area sufficiently having a usable storage capacity from plural block areas. Consequently, it is unnecessary to repeat the block area selection processing and the read processing of selected block areas. Thus, the time required to determine the block area is shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention (Field of Industrial Application) This invention relates to a data storage method for storing data in a database.

(Prior Art) Generally, in computer systems, various data management is performed using a database, and this database is usually stored in a randomly accessible auxiliary storage device such as a magnetic disk device. Data output to this auxiliary storage device is performed in blocks. One block of data consists of multiple records.

When storing data in the auxiliary storage device, first, a block area to be stored is selected in the storage area of the auxiliary storage device. The method for selecting this block area is as follows:
A method for selecting a corresponding block by performing a predetermined operation on specific information provided in each record, and a method for selecting a corresponding block so that each record within one block of data is stored in the same block or adjacent blocks. , or a method of sequentially selecting relevant blocks according to the order in which data is stored is known.

The block area selected in this manner is read from the auxiliary storage device into the internal memory. If the usable storage capacity of the block area read into the internal memory is sufficient, all the corresponding data is stored in that block area.

On the other hand, if the usable storage capacity of the block area is insufficient, records that cannot be stored are generated. in this case,
A new block area is selected again to store the remaining records that could not be stored in another block area.
The block area is read from auxiliary storage into internal memory. However, the usable storage capacity of the newly read block area may not be sufficient to store the remaining records, or there may be no usable storage capacity remaining at all. In such a case, the process of selecting a block area and the process of reading the selected block area are performed again.

In this way, in the past, the usable storage capacity of a block area could not be recognized unless the block area was actually read from the auxiliary storage device into the internal memory, so the block area selection process and its selection were repeated many times. The read process for the block area that has been created must be executed. Therefore, there is a drawback that it takes time to determine a block area that can actually store data.

(Problem to be Solved by the Invention) Conventionally, the usable storage capacity of a block area cannot be recognized unless the block area is actually read from the auxiliary storage device into the internal memory. The disadvantage is that it takes time to make a decision.

The present invention has been made in view of these points, and it is an object of the present invention to shorten the time required to determine a block area in which data can be stored, and to efficiently use the data storage area of an auxiliary storage device at high speed. The purpose is to provide a data storage method that allows for

[Structure of the Invention] (Means for Solving the Three Problems) The data storage method according to the present invention includes a data storage means having a storage area divided into a plurality of blocks, and a reusable storage area and an unused storage area in each block. Block management information storage means storing block management information indicating the capacity and position of each storage area, and area management information indicating the total capacity of both the reusable 6J capacity storage area and the unused storage area for each block. an area management information storage means to be stored; and when storing data in the data storage means, the area management information stored in the area management information storage means is referred to, and information that can be used in a block of the data storage means is stored. The present invention is characterized by comprising a data storage control means for detecting a block including a storage area and storing data in the detected block by referring to the block management storage information.

(Function) In this data storage method, since the area management information storage means stores area management information indicating the total capacity of both the reusable storage area and the unused storage area for each block, this area management information By referring to , a block area having sufficient usable storage capacity can be detected from among a plurality of block areas. Therefore, it is no longer necessary to repeat the process of selecting a block area and the process of reading the selected block area many times, and the time required until the block area is determined can be reduced.

Further, since the block management information storage means stores block management information indicating the capacity and position of the reusable storage area and unused storage area in each block, by referring to this block management information, It becomes possible to effectively use the data area by using both the reusable storage area and the unused storage area.

(Example) Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a system configuration for realizing a data storage method according to an embodiment of the present invention.

A data processing device consisting of a computer! ! , which performs various functions necessary for data processing, is composed of a division/integration processing module 13, an input/output control module 14, a first shared memory 15, and a second shared memory 1B. The division/integration processing module 13 executes division/integration processing in record storage/retrieval processing.

The input/output control module 14 performs input/output control for database data and area management information stored in the auxiliary storage device 12 under the control of the division/integration processing module 13 . The shared memory 15 is for storing database data read from the auxiliary storage device 12, and has a data storage capacity of one block. The shared memory 16 is for storing area management information read from the auxiliary storage device 12, and has a data storage capacity for one block.

The auxiliary storage device 12 stores data constituting a database,
The area for storing the database and the area for storing the area management information are configured as shown in FIGS. 2 and 3, respectively.

As shown in FIG. 2, the database file area 121 of the auxiliary storage device 12 is composed of 64 block areas B1-864, each block area having a storage capacity of 64 bytes. The size of each block area corresponds to the input/output unit of the human output control module 14. Each block area is provided with a block management information storage area Kl, and the remaining area is, for example, a record group area where records are already stored.
It is divided into 3 reusable areas where previously stored records have been deleted and 4 unused areas where no records are stored.

The block management information stored in the block management information storage area Kl indicates the storage capacity and location (address) of 3 reusable areas and 4 unused areas within the block area.

Further, the storage area of area management information in the auxiliary storage device 12 is composed of two area management information blocks C1 and C2, as shown in FIG. has a storage capacity of 64 bytes, which is an input/output unit. Area management information block C
I includes area management information corresponding to block area Bl-832 shown in FIG. In addition, the area management information block C2 includes the block area 8 shown in FIG.
Area management information corresponding to 34 to B64 is included.

Each of the area management information blocks C1 and C2 has "information block No. J", "start block No. J", and "end block No. J" as intra-block management information. This indicates the serial number of area management information blocks. For example, ``1'' is registered in ``Information block No., J'' of area management information block Ct, and ``1'' is registered in ``Information block No., J'' of area management information block C2. “2” is registered. “Start block NO0” indicates the first block area managed by the area management information block, and “end block NO0” indicates the first block area managed by the area management information block.
O1'' indicates the final block area managed by the area management information block. Area management information block CI
is area management information S corresponding to block areas 81 to B32
1 to S32, the "start block No. 2" and "end block No., J" are respectively '
1° and "32". Similarly, since the area management information block C2 includes area management information corresponding to the block areas 834 to B64, the "start block No. J" and "end block No. J" are respectively "
33” and 641.

Each of the area management information blocks C1 and C2 further includes a plurality of area management information corresponding to each block area to be managed. Area management information 5l-3 of area management information block CI (2 indicates the total storage capacity of the reusable area and unused area of block area Bl-832. For example, area management information S2 is The total storage capacity of the block area B2 shown in FIG. 2 is 3 in the reusable area and 4 in the unused area.

Next, the operation of data storage processing by the data processing apparatus of FIG. 1 will be described with reference to the flowchart of FIG. 4.

When data processing device 11 receives a request to store data consisting of a plurality of records, processing for storing the data is entrusted to record division and integration processing module 13. Record division integration processing module! 3, first, a first storage candidate block area is selected by a predetermined selection method according to the record storage conditions (step AI). The storage candidate block area can be selected by, for example, selecting a corresponding block by performing a predetermined operation on specific information provided in each record, or selecting a block where each record in one block of data is in the same block or in adjacent blocks. A method is used in which the relevant blocks are selected so that they are stored in the data, or a method in which the relevant blocks are selected in order according to the order in which the data is stored.

Next, the record division and integration processing module 13 is a human output control module! 4, reads the storage candidate block area, for example, B2, from the auxiliary storage device 12 into the shared memory I5, and refers to the block management information Kl of the read block area B2 to reuse the unused area information of the block area B2. Obtain possible area information (step A2). Then, it is determined whether or not there is a usable area in the block area B2 (step A3), and if there is no usable area, the next candidate block selection process is executed in step A8.
If there is an i usable area, the process advances to step A4.

In step A4, the maximum area size and its position among the unused areas or continuous areas within the reusable area are determined based on the block management information Kl of the block area B2. When this maximum area size is larger than the record to be stored, the record to be stored is transferred to the shared memory 15 and stored in the block area B2 (step A5). In this case, block area B2
Block management information! The size information of the unused area or the size information of the reusable area is decreased by the stored record size. Also, at this time, shared memory 1
If the area management information block CI is stored in the area management information block C1, the area management information S in the area management information block C1
The value of the total size indicated by 2 (area management information S2 corresponds to block area B2) is also reduced by the stored record size.

Next, it is determined whether the storage process for the records to be stored has all been completed (step A8), and if it has been completed, the storage process is finished, and if it has not been completed, the block area B2 that has been read is used. It is determined whether the available area is insufficient (step A7). If there is no shortage of usable area in block area B2, steps A4 to
At A6, data storage processing is repeatedly performed in units of records. On the other hand, if the usable area is insufficient in the block area B2, the next candidate block is selected in step A8.

The next candidate block selection process in step A8 is performed when it is determined in step 3 that there is no usable area for the storage candidate block, or when it is determined that the usable area for the storage candidate block is insufficient in step A7. .Step A8
In the next candidate block selection process, first, the area management information block CI is read from the auxiliary storage device I2,
It is stored in the common H memory 18. Next, a block area including a usable area is searched based on the contents of the area management information Sl-324 of the area management information block CI. This search process is executed sequentially from the area management information next to the area management information corresponding to the first storage candidate block area determined in step AI.

For example, when block area B2 is selected as the first storage candidate block area, search processing is performed from area management information S3.

If a block area including a usable area cannot be searched using the area management information block CI, a similar search process is executed using the area management information block C2.

Then, it is determined whether there is a block area including a usable area (step A9), and if there is no block area including a usable area, record storage is not possible, and error processing is performed. Further, if there is a block area including a usable area, that block area is selected as the next candidate storage block area, and the block area is read from the auxiliary storage device 12 into the shared memory 5 in step A2.

Then, the processes of steps A3 to A7 described above are executed for the next candidate storage block area.

In this way, in this embodiment, the area management information indicating the total capacity of both the reusable storage area and the unused storage area can be stored in the shared memory 16 for each block. By referring to the block area, a block area having sufficient usable storage capacity can be detected from among the plurality of block areas. Therefore, the process of selecting a block area and the process of reading the selected block area are not repeated many times, and the time required until the block area is determined can be reduced.

Further, block management information is set in each block area, and this block management information indicates the capacity and position of each of the reusable storage area and the unused storage area. Therefore, by referring to the block management information, it is possible to effectively utilize the data area by using both the reusable storage area and the unused storage area.

[Effects of the Invention] As described above, according to the present invention, it is possible to shorten the time required to determine a block area in which data can be stored, and moreover, it is possible to effectively use the data storage area of the auxiliary storage device. becomes.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a system configuration for realizing a data storage method according to an embodiment of the present invention, and FIG. 2 is a configuration of a database storage area in an auxiliary storage device provided in the system of FIG. 1. FIG. 3 is a diagram showing the configuration of the area management information storage area in the auxiliary storage device provided in the system of FIG. 1, and FIG. 4 explains the data storage processing operation of the system of FIG. 1. It is a flowchart. DESCRIPTION OF SYMBOLS 11... Data processing device, 12... Auxiliary storage device, 13... Division and integration processing module, 14... Human output control module, 15° 1B... Shared memory.

Claims (1)

[Claims] a data storage means having a storage area divided into a plurality of blocks; a block management information storage means in which block management information indicating the capacity and position of each of the reusable storage area and unused storage area in each block is stored;
an area management information storage means in which area management information indicating the total capacity of both the reusable storage area and the unused storage area for each block is stored; and when storing data in the data storage means, the area management information A block including a usable storage area is detected among the blocks of the data storage means by referring to the area management information stored in the storage means, and the block management storage information is referred to for the detected block. 1. A data storage method comprising: a data storage control means for storing data.