JPH064381A - Variable length record replacing system - Google Patents

Abstract

PURPOSE:To replace arbitrary records constituting a member with the records of different length. CONSTITUTION:A replacement processing means 12 replaces the arbitrary record in a member 15, which is composed of plural blocks composed of plural records, with the record of the different length by packing the records in the block in the case of the short record or by adding a block in the case of the long record. Then, a storage processing means 13 and an addition processing means 14 can be added not to prepare any useless blocks in the case of storing and adding the block.

Description

Detailed Description of the Invention

[0001]

This invention relates to library management,
In particular, it relates to a variable length record replacement method for realizing member access to a library.

[0002]

2. Description of the Related Art In the past, when a variable length record was used, it was not possible to replace an arbitrary record constituting a member unless the record had the same length. Even in the case of replacing only one record, one member is updated, and a new member is temporarily created and then the member before updating is deleted.

[0003]

In the above-mentioned conventional method, when the record is composed of variable length records, it is not possible to replace arbitrary records constituting the member unless the records have the same length. For this reason, even in the case of replacing only one record, all the records must be read and written from the head of the member, and there is a problem that the processing takes a considerable amount of time. In addition, since one member is updated, there is a problem that a sufficient area is required to create a temporary new member.

[0004]

According to the variable length record replacement method of the present invention, for a member consisting of variable length records in a library of standby join organization, any record constituting this member is replaced with a short record. When this is done, the records in the block are packed, when a long record is replaced, a new block is added, and a replacement processing means is provided for replacing an arbitrary record constituting a member with a record of a different length. Also, in the variable length record replacement method according to another invention of the present invention, in the above-mentioned one, when replacing an arbitrary record constituting a member with a long record, if the total of the record lengths is equal to or less than the block length, a new block is added. It is provided with a storage processing means for storing in the block without adding. A variable-length record replacement method according to yet another invention of the present invention is the variable-length record replacement method according to the first invention, wherein when replacing an arbitrary record that constitutes a member with a long record, the record length to be written in a new block is If it fits in this block, it is provided with additional processing means that does not add a new block.

[0005]

In the present invention, any record that constitutes a member is replaced with a record having a different length.

[0006]

FIG. 1 is a block diagram showing an embodiment of the present invention. In FIG. 1, 11 is a record, and 12 is a variable-length record member in the library of standby join organization. When replacing any record that constitutes this member with a short record, the record in the block is This is a replacement processing unit that adds a new block when replacing a record with a long record and replacing an arbitrary record forming a member with a record having a different length. Reference numeral 13 is a storage processing means for storing an arbitrary record constituting a member into a block without adding a new block if the total record length is equal to or smaller than the block length, and 14 is a member. This is an additional processing means that does not add a new block if the record length to be written in a new block fits in the next block when replacing an arbitrary record to be composed with a long record. Reference numeral 15 is a member consisting of variable-length records in the library of the standby join organization.

The member 15 in the library of the standby connection organization is composed of a plurality of blocks each having a variable length record, and each block is connected by a chain. The present invention uses the replacement processing means 12 to
It is possible to replace an arbitrary record forming the member 15 with a record having a different length.

FIG. 2 is an explanatory diagram showing the member structure before and after replacement, and shows an example of the member structure before and after replacement by the replacement processing means 12 of FIG. Here, the case where the record B is replaced with the record F whose record length is longer than the record B is shown. FIG. 2A shows an example of the member structure before replacement. The member is composed of a plurality of blocks (block 1 and block 2 in the figure). Each block is composed of a plurality of records (block 1 is record A, record B, record C, and block 2 is record D, record E). Each block is connected by a chain. FIG. 2B shows an example of the member structure after the replacement, and shows a state in which the record B in FIG. 2A is replaced with the record F. The previous record (record A in the figure) that precedes the record to be replaced in the block and the record to be replaced (record B in the figure)
And a succeeding record (record C in the figure) located after the record to be replaced are divided into three blocks, and the contents of the block of the record to be replaced (block 4 in the figure) are designated and replaced. (Record F in the figure).

FIG. 3 is a flow chart for explaining the operation of the replacement processing means 12 in FIG. Next, FIG.
The process from FIG. 2A to FIG. 2B will be described with reference to FIG. (1) The size of the record to be replaced (old record) is compared with the size of the record to be replaced (new record) (step 101). In FIG. 2, the old record is record B,
The new record is record F. (2) When the results of (1) are the same, the replacement is performed by the conventional processing. (Step 102). (3) As a result of (1), when the new record is shorter than the old record, first, a new block (new block) is secured (step 103). Then, the records in the block including the record to be replaced with the new block are sequentially copied and stored. (Step 104). At this time, the old record is replaced with the new record. The chain is changed so that the new block becomes a member's constituent block and the old block is released (step 105). (4) As a result of (1), if the new record is longer than the old record, the previous record, the old record, and the subsequent record are 3
Replace old record with new record. Figure 2
Then, since the record F is longer than the record B, this condition is processed. The previous record is the record A and the subsequent record C. If the old record (record B in FIG. 2) is not the last record of the block (block 1 in FIG. 2) but the succeeding record (record C in FIG. 2), the member has a block (FIG. 2). A block 3) is added and the subsequent records are copied and stored (steps 106 and 107).

If the old record (record B in FIG. 2) is not the head record of the block (block 1 in FIG. 2) but the previous record (record A in FIG. 2), the member is blocked. (Block 4 in FIG. 2) is added to store a new record (record F in FIG. 2).
If the old record is the first record in the block, the new record is stored from the beginning of the block (step 10).
8, 109). Last block (block 1 in Figure 2)
The record (record B and record C in block 1 in FIG. 2) subsequent to the previous record (record A in FIG. 2), which is an unnecessary area, is deleted to make an empty area (steps 110 and 111). ). Through the above processing, it is possible to replace any record that constitutes a member with a record having a different length. Moreover, the maximum free area in the library required for processing may be two blocks.

Next, the storage processing means 13 and the addition processing means 14 as functions that can be added to the present invention will be described. 4A and 4B are explanatory views showing the member structure by the storage processing means 13, wherein FIG. 4A shows the member structure before the processing, and FIG. 4B shows the member structure after the processing (record B is replaced with record G). In the figure, only the block including the record to be replaced is shown. The block includes a previous record (record A in the figure) before the record to be replaced, a record (record B in the figure) to be replaced, and a succeeding record (record C in the figure) to be replaced. ). When an arbitrary record (record B in the figure) constituting a member is replaced with a long record (record G in the figure), if the total record length is equal to or less than the block length, a new block is not added. Place in a block.

FIG. 5 is a flow chart for explaining the operation of the storage processing means 13 and shows the portion to which the processing is added to FIG. The size of the record to be replaced (old record) and the size of the record to be replaced (new record) are set in Step 20.
If the new record is longer than the old record as compared with 1, the sum of the record lengths included in the block after replacement (the sum of record A, record G, and record C in FIG. 4) and the block including the empty area Compare with length (step 20)
2). Then, when the sum of the record lengths in the block is shorter than the block length, the process when the new record is shorter than the old record ((3) in FIG. 3) is performed. If the sum of the record lengths in the block is longer than the block length,
The processing when the new record is longer than the old record ((4) in the description of FIG. 3) is performed. As is clear from the above explanation,
Since the storage processing unit 13 does not create useless blocks, the area of the library can be effectively used.

FIG. 6 is an explanatory view showing a member structure by the addition processing means 14, and FIG. 6A shows a member structure before processing,
(B) shows the member structure after processing (record B to record H
Replaced). Block 1 includes a previous record (record A in the figure) before the record to be replaced, a record (record B in the figure) to be replaced, and a subsequent record (record in the figure to be replaced) after the record to be replaced. It shall include three records of C). When an arbitrary record (record B in the figure) forming a member is replaced with a long record (record H in the figure), if the record length to be written in the new block is within the next block, the new block Is not added. In FIG. 2, the subsequent record (record C in the drawing) is stored by adding a new block (block 3 in the drawing), but in FIG. 6, the new block is not added and is stored in block 2. .

FIG. 7 is a flow chart for explaining the operation of the additional processing means 14, and FIG. 3 shows a portion to which the processing is added. FIG. 7A is a flowchart of the block addition process when storing the subsequent record, which is added to the process of adding the block and storing the subsequent record in FIG. The size of the block is compared with the sum of the sizes of the succeeding record (record C in FIG. 6) after the record to be replaced and the record (record D in FIG. 6) in the next record (step 30).
1). If it is longer than the block size, the same block as in FIG. 3 is added and the subsequent record is stored (step 302). If the block size is shorter than the block size, first, a new block (new block) is secured (step 303). The continuous record and the record in the next block are sequentially copied and stored in the new block (step 304). The chain is changed so that the new block becomes a constituent block of the member and the old block is released (block 2 in FIG. 6) (step 305).

FIG. 7B is a flow chart of the block addition process when storing a new record, which is added to the process of adding a block and storing a new record in FIG. The sum of the sizes of the previous record (record A in FIG. 6) and the new record (record H in FIG. 6) to be replaced is compared with the block size (step 306). If it is longer than the block size, the same block as in FIG. 3 is added and a new record is stored (step 3
07) and continues to the next process in FIG. If the block size is shorter than the block size, a new block (new block) is secured first (step 308). The previous record and the new record are sequentially copied and stored in the new block (step 30).
9). Then, the chain is changed so that the new block becomes a member constituent block and the old block is released (step 310) (block 1 in FIG. 6). As is apparent from the above description, since the additional processing means 14 does not create useless blocks, the area of the library can be effectively used.

[0016]

As described above, according to the present invention, any record forming a member is replaced with a record having a different length. On the other hand, it is possible to replace any record that constitutes a member with a record of a different length, and in the case of replacing only one record, it is not necessary to read and write all the records from the head of the member. Therefore, there is an effect that the processing time can be shortened. Further, since one member is not newly created, there is an effect that update processing can be performed in a small area.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an example of a member configuration before and after replacement, which is used for explaining the operation of FIG.

FIG. 3 is a flowchart for explaining the operation of a replacement processing unit in FIG.

FIG. 4 is an explanatory diagram showing a member configuration example of a storage processing unit in FIG.

5 is a flowchart for explaining the operation of the storage processing means in FIG.

6 is an explanatory diagram showing an example of a member configuration by the addition processing means in FIG.

FIG. 7 is a flowchart for explaining the operation of the additional processing means in FIG.

[Explanation of symbols]

 11 Record 12 Replacement Processing Means 13 Storage Processing Means 14 Additional Processing Means 15 Members

Claims (3)

[Claims] 1. When a member consisting of variable-length records in a library of the standby join organization is replaced with a short record for any record constituting the member, the records in the block are packed and replaced with a long record. The variable-length record replacement method is characterized by comprising a replacement processing means for adding a new block to replace an arbitrary record constituting a member with a record having a different length. 2. The variable length record replacement method according to claim 1, wherein when an arbitrary record constituting a member is replaced with a long record, if the total of the record lengths is equal to or smaller than the block length, a new block is not added. A variable-length record replacement method, characterized in that a storage processing means for storing the data in a block is provided. 3. The variable length record replacement method according to claim 1, wherein when an arbitrary record forming a member is replaced with a long record, if a record length to be written in a new block is within the next block, a new record is added. A variable-length record replacement method characterized by comprising additional processing means for adding no block.