JPH02120931A - External file allocation system for sort - Google Patents

Abstract

PURPOSE:To effectively utilize a sorting external file to be a system resource by providing the title system with a sorting external file control means for securing an external file when necessary. CONSTITUTION:Data are inputted from an input file 1 to a sort processing executing means 3, which sorts data while storing them. When the means is satisfied with data, the sorting external file control means 7 secures an external work file 9 and temporarily save sorting intermediate data stored in the means 3 in the file 9. As the result, the input data are stored in the file 9 as an intermediate result for sort. Since the external file is allocated only at the time of using the file for sorting, the allocation time of the external file occupied by sorting is reduced and, during the time the resource is utilized by other program. Thus, the resource is effectively utilized by the whole system.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an external file allocation method for sorting,
In particular, it relates to an effective allocation method for external files for sorting, which are system resources.

[Conventional technology]

The conventional sorting program was realized by the following (1) to (3).

(1) Check whether all the resources (minimum work memory, input file, output file, external work file) expected to be necessary for the sort environment have been allocated before executing the sort. If it is not allocated, processing will be interrupted.

(2) Input data from the allocated input file, store it in the work memory, and sort it. If the data cannot be stored in the work memory, temporarily save the intermediate data for sorting in the allocated work file. . When all the data can be stored in the work memory, the sorted data is not output to the allocated external work file, but is output as is to the output file.

(3> Once the intermediate sort data is saved in the allocated external work file, the external work file and work memory are used to sort all input data in ascending/descending order and output it to the output file. do.

[Problem to be solved by the invention]

In the conventional external file allocation method described above, at the beginning of program execution, the sort environment such as external files, which are the elements that determine the sort method and the input/output method to the sort input/output file, is checked, so there is a possibility that the external file will not be used. An external work file must also be installed from the start of execution, and an output file that only needs to be installed when outputting the sorted result data must also be installed from the start of execution. In this way, there is a drawback that unused resources are occupied for a long time.

[Means to solve the problem]

The configuration of the external file allocation method for sorting of the present invention includes a sort environment control means that inspects specified parameters and file attributes of allocated input files and output files, and determines the input/output method, and this sort environment control means. a sorting input processing means that reads data one by one from the input file using the input method determined by and releases the input file when all the data has been read;
sorting execution control means for inputting the data read by the sorting input processing means and sorting the data;
The data sorted by the sort execution control means is received one by one from the sort execution control means, and when an external file cannot be secured, the output method is determined by the sort environment control means. a sort output processing means that outputs data one by one to an output file secured according to file information instructing whether to The present invention is characterized in that it includes a sorting external file control means for securing the external file when necessary according to the file information, such as waiting until the external file can be secured or interrupting when the external file cannot be secured.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of the present invention, in which 1 is an input file in which input data is stored, 2 is an input file in which input data is read one by one, and the data is sent to a sort execution unit in 3. Sorting input processing means 3 sorts the data transferred from 2, and outputs the intermediate results to 8.
Data is temporarily saved to an external work file through the work file input/output processing means (this step is called presort), or data is sorted using the external work file and work memory (this is called collision). ,
Also, a sort processing execution means (referred to as last pass) transfers the final result to the sort output processing means 4, and a sort output processing means 4 writes the data transferred from the sort processing execution means 3 to the output file 5. , 6 is a sort environment control means that checks the initial state of external files for sorting, work memory, etc. and determines the sorting method, and 7 is a sorting environment control means that manages the status of external files for sorting and can be secured when an external file cannot be secured. 8 is a work file input/output processing means that performs input/output to an external work file; 9 is a 7 This is an external work file that has been secured or previously allocated by the external file control means.

Consider an example in which a large amount of input data is stored on a magnetic tape, a reasonably large work memory can be secured, a magnetic disk is used for external work files, and the sort results are output to the magnetic tape.

Before starting the sorting process, the environment checks whether the work memory size is sufficient and the input file is installed, and the remaining information necessary for determining the sorting method (sorting procedure when an external file cannot be secured, output file information) is Input it as a program parameter. In this manner, after receiving permission to execute the sort from the sorting environment control means 6, the sorting process is started.

Data is input from the input file 1 into the sort processing execution means 3. Here, we will sort the data while storing it. When this becomes a cup and can no longer be stored,
The sort external file control means 7 secures an external work file from the system. Once secured, the sort intermediate data in the sort processing execution means in step 7 is saved to an external work file. Read the next data into the free work memory and continue sorting. Repeat the same process and perform input processing for all input data.

As a result, the input data is stored in the external work file 9 as an intermediate result of sorting. Input file 1 can be removed from the magnetic tape device if specified. Sorting of the data stored in the external work file 9 is completed using the work memory in the sort processing execution means of the external work file 7. The sort external file control means 7 secures a magnetic tape device for output files from the system. Once secured, attach the output magnetic tape and output the sort results. After using the external work file, release the external work file and finish sorting.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, there is provided a sort external file control means that manages the allocation status of external files used in sorting and secures external files when necessary according to the file information. Since external files are allocated only when they are used, the time taken up by sorting to allocate external files is reduced, and during this time other programs can use the resources, which has the effect of making more efficient use of resources for the system as a whole. .

[Brief explanation of the drawing]

FIG. 1 is a block diagram of one embodiment of the present invention. 1...Input file, 2...Sort input processing means, 3
...Sort processing execution means, 4.Sort output processing means, 5.Output file, 6.Sort environment control means, 7.Sort external file control means, 8.Work file input. Output control means, 9...external work file.

Claims (1)

[Claims] A sorting environment control means that inspects specified parameters and file attributes of allocated input files and output files, and determines the input/output method;
sorting input processing means that reads data for one case and releases the input file when all the data is read; and sorting execution control means that inputs the data read by the sorting input processing means and sorts the data. , Receive data sorted by this sort execution control means one by one from the sort execution control means, and use the output method determined by the sort environment control means to wait until an external file can be secured or abort when an external file cannot be secured. a sort output processing means for outputting data one by one to an output file secured according to file information that instructs whether the external file is to be secured; A sorting external file allocation method comprising: a sorting external file control means for securing the external file when necessary according to the file information, such as waiting until the external file can be secured or interrupting when the external file cannot be secured.