JPH0267647A - Exclusive control system for plural records - Google Patents

Abstract

PURPOSE:To shorten a queuing time by providing the title system with processing for locking data records without accessing them and processing for collectively unlocking index records which are not objects for updating processing. CONSTITUTION:In order to find out the record number of a record satisfying the condition of (item - 1) 100, the index of (item - 1) is retrieved 100 times, an index record i1 -1 is accessed and searched and the just preceding value 010 of a value first exceeding the value 100 is found out. In order to find out the record number of a record satisfying the condition of (item - 2) < K, the index of (item - 2) is retrieved by K, an index (i2 - 1) is accessed and searched and the just preceding value A of a value first exceeding K is found out. The AND operation of the record numbers found out by the processing is executed and, record numbers R11, R12 satisfying both the conditions are found out and the records with the number R11, R12 are locked without accessing the records. Records which are not objects for updating processing out of records constituting the indexes of (item - 1) and (item - 2) are collectively unlocked.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an exclusive control method for multiple records, and in particular, to a method for controlling exclusive control of multiple records, in particular, a method for controlling records by searching from a data file stored in a randomly accessible storage device and having multiple indexes. This relates to an exclusive control method for multiple records.

[Conventional technology]

Conventionally, in this type of exclusive control method, when an index is used to find a data record that satisfies a condition, a lock is placed only on the index record accessed during the search process.
No locks are placed on the determined data records. Therefore, in order to prevent the items targeted for search processing in the desired data record from being updated by other users and spoiling the meaning of the data, users must clearly specify the locks they have applied to index records. It was supposed to be retained until it is released.

[Problems to be solved by the invention C] In the conventional exclusive control method described above, the lock applied to the index record is held while the first user is processing it, , it is necessary to wait for the first user to finish processing, but since it locks the index record, its influence is wide, and when searching using the index, it is necessary to access the file and process the data record. There is a high probability that waiting time will be added to the time spent waiting for a meeting, and for example, if the response time in online real-time processing becomes longer, there will be a drawback.

[Means to solve the problem]

The method of the present invention is a process for locking data records without accessing them in an exclusive control method for multiple records determined by search processing from a data file having multiple indexes stored in a randomly accessible storage device. The method is characterized in that it includes a process of collectively releasing locks of index records that are not subject to update processing among index records that have already been locked.

〔Example〕

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

FIG. 1 is a diagram showing the processing method of the present invention. According to Fig. 1, Fig. 2 shows the processing when searching for a record that satisfies the conditions of item - 1 > = 100 AND item 2 - "K゛°" for a file that has two indexes shown in Fig. 2. I will explain using

(1) Search the item-1 index for 100 to find the number of the record that satisfies the condition of item-1>=100.

The index record 11-1 is accessed, and the value 010 immediately before the value exceeding 100 is found by searching therein. value 0
The index record 1l-21 specified by the pointer 10 is accessed and searched to find the value 090 immediately before the value exceeding 100. The index 1l-33 specified by the pointer with the value 090 is accessed, and the value of item-1 is 100.
Find the record number R10.

Next, index record 1l-3 having a value of 100 or more
4, 1l-35, 1l-361l-37, and 1l-38 are accessed in this order, and RIO to R32, which are the numbers of records in which the value of item-1 is 100 or more, are obtained.

Index records 1l-1, 1l-21, 1133, 1l-3 that constitute the item-1 index accessed through this process
4, 1l-35, 1l-36゜1f-37, 1l-38
A lock is implemented as shown by el in FIG.

(b) Search the item-2 index for "K" to find the number of the record that satisfies the condition of item-2.

Access index 12-1 and search within it for the first time.
Find the value "A'" immediately before the value exceeding . Next, index record 12-21 is accessed and searched therein to find the value II II I+ that is the one before the value exceeding "K''. Next, index record 12-33 is accessed and the value of item-2 is found. Find the number R11 of the record whose value is "°". Finally, index records 12-32 and 12-31 are accessed in order, and the record numbers R11, RIO, R9, R8, R7, R6, R5 where the value of item-2 is less than °゛K''
, R4, R3, R2, and R1.

Through this process, the index records 12-1, 12-21°i2 31. which constitute the accessed item-2 index. i2
32. A lock is implemented for i2 33 as shown at 22 in FIG.

(c) Perform an AND operation on the record numbers obtained in the processes of (a) and (b) to obtain record numbers R11 and R12 that satisfy both conditions.

Next, the records with record numbers R11 and R12 are locked without being accessed.

Through this process, the records of R11 and R12 are as shown in Figure 2! ! A lock is implemented as shown in 3.

(d) Among the records constituting the item-1 index 2 item-2 index, records that are not subject to update processing are unlocked all at once.

Through this process, index records 1l-1, 1l-21゜1l-33, 1 constituting item index-12 item index-2
l-34, 1l-35, 1l-36, 1l-37, 1l
-38,12-1,1221,1l-31,12-32
, 12-33 are released.

〔Effect of the invention〕

As explained above, the present invention prevents updates from other users by locking desired data records through index processing, guarantees the validity of search results,
Afterwards, by releasing locks on index records that are not subject to update processing among the locks held on index records used in search processing, subsequent users who perform searches using the index can Lower the probability that the first user will access the locked record,
This has the effect of shortening the waiting time.

[Brief explanation of the drawing]

FIG. 1 is a flowchart illustrating the present invention, and FIG. 2 is a diagram illustrating a lock state transition in a file having two indexes. 11-1 to 1l-38... Index of item-1, 12
-1 to 12-38...index of item-2, R1 to R32...data record, er, e2°! ! 3.
··rock. Agent Fu 1 Buried by Susumu Jouchihara/Figure

Claims (1)

[Claims] In an exclusive control method for a plurality of records obtained by a search process from a data file having a plurality of indexes stored in a randomly accessible storage device, a process for locking without accessing the data records; 1. An exclusive control method for a plurality of records, characterized by including a process for collectively releasing locks on index records that are not subject to update processing among index records that have already been locked.