CN109446294A - A kind of parallel mutual subspace Skyline querying method - Google Patents
A kind of parallel mutual subspace Skyline querying method Download PDFInfo
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Abstract
The invention discloses a kind of parallel mutual subspace Skyline querying methods.This method utilizes the sequential access method of B+ tree index, and mutual subspace Skyline inquiry is realized in parallel query environment.In spatial data, a B is established to each dimension i of all data objects+Tree index BDi-tree is with the coordinate value of the sequential access dimension.The traversal strategies of B+ tree index technology and distance priority are utilized, first seek dynamic subspace Skyline, then negate to subspace Skyline, realize parallel mutual subspace Skyline querying method.User can retrieve mutual subspace data object according to specified query object, and provide best performance.
Description
Technical field
The present invention relates to the indexes and inquiring technology in spatial database, more particularly to a kind of parallel mutual subspace
Skyline inquiry method.
Background technique
Spatial database is the Database Systems of storage and management spatial data.It is a large amount of in order to quickly and efficiently access
Spatial database, experts and scholars propose a large amount of space index method, wherein having R tree index, R* tree index, K-D-B tree rope
Draw, and the B+ tree index of single dimension.On this basis, various inquiries and its solution with their own characteristics are more proposed,
Such as NN Query, k NN Query, Continuous Nearest Neighbors Inquiry, Skyline inquiry.
With the fast development of computer, communication, internet and location technology, a large amount of data are in scientific algorithm, society
It can live and be constantly be generated with fields such as industrial productions.Based on these data, we can construct various complicated and multiplicity intelligence
It can processing system.It is just basic and important at one to go out qualified data according to certain specific binding characteristic quick-searching
The problem of namely database in inquiry problem.
In these inquiries, Skyline inquiry is closely related with NN Query, it retrieves one from a data concentration
Optimal subset can not find another data object each so that arbitrary data object therein is all irreplaceable in other words
All than its " good " on data dimension.Skyline inquiry is sought in multiobjective decision-making, business data analysis, user preference support, market
Pin, development of games, most optimum distribution of resources, user interest matching, ambient condition monitoring, urban planning, position selection service and
Data mining and data visualization etc. have broad application prospects and potential economic value.
Currently, Skyline inquiry is only (anti-from the opposing angular of the angle of user (Skyline inquiry) or query object q
Inquired to Skyline) it is handled.However, in necks such as the cloud computing service matchings and social networks individual matching having a extensive future
Domain, Skyline inquiry mode so are not able to satisfy the query demand of service both sides, this needs mutual Skyline inquiry.
Further, mutual Skyline also needs to handle the inquiry in subspace, and the reference point of user and reversed
Reference point can be different, this is mutual subspace Skyline inquiry.Especially in parallel environment, there do not have to be a kind of suitable
Method is inquired to solve mutual subspace Skyline.
Summary of the invention
The purpose of the present invention is to provide a kind of parallel mutual subspace Skyline querying methods.
The step of the technical scheme adopted by the invention to solve the technical problem is as follows:
Step 1) establishes the B of an entitled BDi-tree according to the coordinate value of each dimension i to all data objects+
Tree index, in order to according to the coordinate value of the far and near sequential access data object i-th dimension of Distance query object；
Step 2) is according to user's reference point quInitial position concurrently traverse BDi-tree index, traversal follows distance ginseng
The principle that the closer examination point the more preferential and each dimension is synchronous；
Step 3) calculates the dynamic subspace Skyline of user's reference point, safeguards its object set S1, calculating process is adopted
Redundancy is avoided to scan with virtual point VP；
Step 4) is according to back-reference point qrInitial position concurrently again traverse BDi-tree index, traversal strategies and
Above-mentioned step 2) is identical；
Step 5) calculates the reversed subspace skyline of back-reference point, safeguards object set S2, and calculating process is first demanded perfection
The Skyline object in police station space eliminates the data object of non-return subspace Skyline further according to trimming strategy；
The intersection of step 6) set of computations S1 and set S2, i.e., by non-return subspace Skyline object from set S1
It disposes, obtains mutual subspace Skyline the results list of update.
Traversal strategies in the step 2) refer to that the sequencing of access index interior joint and multiple dimensions are visited
How access stepping is controlled when asking；Three kinds of situations of the strategy point consider:
1) in the same dimension, when the not visited left side node at a distance from query point than not visited the right
Node more hour at a distance from query point first accesses the node on the left side, otherwise the node on access the right；
2) in the same dimension, when the node on the not visited left side is equal to the not visited right side at a distance from query point
When mid-side node is at a distance from query point, the node of the right and left accesses respectively；
3) it in different dimensions, is accessed according to the far and near ascending order of not visited node and query point distance.Particularly,
The L1 distance of not visited node and query point is calculated after access every time；In all dimensions, there are not visited node and inquiry
When the distance minimum of point, the node in the dimension is first accessed until not visited node at a distance from query point in all dimensions
In when reaching maximum until.
Calculating reference point q in the step 3)uDynamic subspace Skyline the step of include:
1) according to references object quThe coordinate value q of dimension iu[i] concurrently obtains it in the initial access position of each dimension
And q it sets, i.e.,uCoordinate value position on the immediate BDi-tree of [i] coordinate value；
2) a group access node is concurrently obtained according to index traversal strategies, and saved in lists, calculate each dimension
Virtual point VP；
3) for the current group node in list, the dynamic subspace of its part is calculated according to dynamic skyline method
Skyline point；
4) with virtual point test and dynamic skyline method, on the dynamic subspace Skyline point of part, parallel
Ground calculates dynamic subspace Skyline, safeguards the dynamic subspace Skyline set of reference point；
5) using the dynamic subspace Skyline point of part, concurrently judge reference point quDynamic subspace Skyline
Whether terminate.If meeting specified condition, reference point q is terminateduDynamic subspace Skyline calculate, obtain its result
Set S1.
Calculating reference point q in the step 5)rReversed subspace Skyline the step of include:
1) according to back-reference object qrThe coordinate value q of dimension ir[i] concurrently obtains it in the initial access of each dimension
Position, i.e., and qrCoordinate value position on the immediate BDi-tree of [i] coordinate value；
2) a group access node is concurrently obtained according to index traversal strategies, and be distributed in the list of each subregion, point
Area is obtained according to the relative positional relationship of reference point coordinate and current data point coordinate；
3) data object in each subregion is handled, back-reference point q is obtainedrReversed subspace in Skyline pairs
As, including the processing of four steps:
A) it is directed to the data object of each subregion, calculates its global subspace Skyline object；
B) for global subspace Skyline object, if it is only scanned once, pass through dynamic subspace
Object in Skyline set S1 judges whether it is reference point q according to specified conditionrReversed subspace in
Skyline object；
C) for global subspace Skyline object, if be scanned in all dimensions of whole subspaces once,
Reversed subspace Skyline is then terminated to calculate；
D) reference point q is safeguardedrReversed subspace in Skyline object, obtain its results set S2.
User's reference point q in the step 2)uWith the back-reference point q in step 4)rIt can be the same data pair
As being also possible to different data objects, they may be in same sub-spaces, also may be at different subspaces
In.
Step 5) the conditional is the object tested in the dynamic subspace Skyline set currently obtained and virtual
The control planning of point VP, including two kinds of situations:
1) there are the virtual point VP phases of the corresponding subregion of data object r in a dynamic subspace Skyline set
Deng；
2) there are data object r with respect to user's reference point quControl its virtual point VP for corresponding to subregion.
B) condition of step is to judge whether current data object is the reversed sub empty of back-reference point in the step 3)
Between Skyline object, condition requires arbitrary data object in S1 in user's reference point subspace opposite in any dimension
The global subspace Skyline object of back-reference point " is not controlled " partly in back-reference point；If condition is that very, this is dynamic
Label is set in state subspace Skyline data object, show be not mutual subspace Skyline object.
The invention has the advantages that:
The present invention takes full advantage of existing B+ tree index technology in database, Skyline inquiry and reversed Skyline and looks into
The research of inquiry and Realizing Achievement provide a kind of mutual subspace Skyline inquiry based on B+ tree index in parallel environment
Method, to meet the needs of both sides Skyline inquiry, user can execute according to dynamic select query object and subspace
Efficient mutually subspace Skyline inquiry.
Detailed description of the invention
Fig. 1 is the implementation steps of the invention flow chart；
Fig. 2 is a kind of parallel mutual subspace inquiry operation principle schematic diagram provided by the invention.
Specific embodiment
Below in conjunction with attached drawing, the technical characteristic and advantage above-mentioned and other to the present invention are clearly and completely described,
Obviously, described case study on implementation is only part case study on implementation of the invention, rather than whole case study on implementation.
Technical solution of the present invention is described further now in conjunction with attached drawing and specific implementation.
As shown in Figure 1, specific implementation process of the present invention and working principle are as follows:
Step 1) establishes the B of an entitled BDi-tree according to the coordinate value of each dimension i to all data objects+
Tree index, in order to according to the coordinate value of the far and near sequential access data object i-th dimension of Distance query object；
Step 2) is according to user's reference point quInitial position concurrently traverse BDi-tree index, traversal follows distance ginseng
The principle that the closer examination point the more preferential and each dimension is synchronous；
Step 3) calculates the dynamic subspace Skyline of user's reference point, safeguards its object set S1, calculating process is adopted
Redundancy is avoided to scan with virtual point VP；
Step 4) is according to back-reference point qrInitial position concurrently again traverse BDi-tree index, traversal strategies and
Above-mentioned step 2) is identical；
Step 5) calculates the reversed subspace skyline of back-reference point, safeguards object set S2, and calculating process is first demanded perfection
The Skyline object in police station space eliminates the data object of non-return subspace Skyline further according to trimming strategy；
The intersection of step 6) set of computations S1 and set S2, i.e., by non-return subspace Skyline object from set S1
It disposes, obtains mutual subspace Skyline the results list of update.
Data object to be treated in the present invention, as shown in the index module of Fig. 2, using the dimension of B+ tree in step 1)
Degree index, is established by keyword of each latitude coordinates value of data object.
Traversal strategies in step 2) refer to when the sequencing of access index interior joint and multiple dimensions access such as
What control access stepping；Three kinds of situations of the strategy point consider:
1) in the same dimension, when the not visited left side node at a distance from query point than not visited the right
Node more hour at a distance from query point first accesses the node on the left side, otherwise the node on access the right；
2) in the same dimension, when the node on the not visited left side is equal to the not visited right side at a distance from query point
When mid-side node is at a distance from query point, the node of the right and left accesses respectively；
3) it in different dimensions, is accessed according to the far and near ascending order of not visited node and query point distance.Particularly,
The L1 distance of not visited node and query point is calculated after access every time.In all dimensions, there are not visited node and inquiry
When the distance minimum of point, the node in the dimension is first accessed until not visited node at a distance from query point in all dimensions
In when reaching maximum until.
Following calculating reference point quDynamic subspace Skyline, by the parallel dynamic subspace in Fig. 2
Skyline module, which calculates, to be obtained, and the specific step that calculates includes:
1) according to references object quThe coordinate value q of dimension iu[i] concurrently obtains it in the initial access position of each dimension
And q it sets, i.e.,uCoordinate value position on the immediate BDi-tree of [i] coordinate value；
2) a group access node is concurrently obtained according to index traversal strategies, and saved in lists, calculate each dimension
Virtual point VP；
3) for the current group node in list, the dynamic subspace of its part is calculated according to dynamic skyline method
Skyline point；
4) with virtual point test and dynamic skyline method, on the dynamic subspace Skyline point of part, parallel
Ground calculates dynamic subspace Skyline, safeguards the dynamic subspace Skyline set of reference point；
5) using the dynamic subspace Skyline point of part, concurrently judge reference point quDynamic subspace Skyline
Whether terminate.If meeting specified condition, reference point q is terminateduDynamic subspace Skyline calculate, obtain its result
Set S1.
The basis that the dynamic subspace Skyline set S1 of acquisition is calculated as mutual subspace Skyline, from wherein going
Fall can't be the data object of the reversed subspace Skyline of back-reference point, remaining part is mutual subspace
The query result of Skyline.
The traversal index of step 4) is still the B+ tree index of every dimension in Fig. 2 index module, traversal it is tactful also with
Step 2) is identical, the difference is that reference point, is back-reference point, i.e., the reference point of reversed subspace Skyline inquiry.
Next, back-reference point q is calculatedrReversed subspace Skyline, by reversed subspace parallel in Fig. 2
Skyline module calculates, and whether the purpose is to judge the data object in S1 also in back-reference point qrReversed subspace in
Skyline.If it was not then showing it not is mutual subspace Skyline to data object tag current in S1.Tool
The calculating step of body includes:
1) according to back-reference object qrThe coordinate value q of dimension ir[i] concurrently obtains it in the initial access of each dimension
Position, i.e., and qrCoordinate value position on the immediate BDi-tree of [i] coordinate value；
2) a group access node is concurrently obtained according to index traversal strategies, and be distributed in the list of each subregion, point
Area is obtained according to the relative positional relationship of reference point coordinate and current data point coordinate；
3) data object in each subregion is handled, back-reference point q is obtainedrReversed subspace in Skyline pairs
As, including the processing of four steps:
A) it is directed to the data object of each subregion, calculates its global subspace Skyline object；
B) for global subspace Skyline object, if it is only scanned once, pass through dynamic subspace
Object in Skyline set S1 judges whether it is reference point q according to specified conditionrReversed subspace in
Skyline object；
C) for global subspace Skyline object, if be scanned in all dimensions of whole subspaces once,
Reversed subspace Skyline is then terminated to calculate；
D) reference point q is safeguardedrReversed subspace in Skyline object, obtain its results set S2.
User's reference point q in step 2)uWith the back-reference point q in step 4)rIt can be the same data object,
It can be different data object, they may be in same sub-spaces, also may be in different subspaces.
Query analyzer in Fig. 2 first traverses parallel on index and executes dynamic subspace Skyline, then exists again
It is traversed parallel on index and executes reversed subspace Skyline.
The dynamic subspace that the condition test in step 5) that dynamic subspace Skyline in Fig. 2 is calculated currently obtains
The control planning of object and virtual point VP in Skyline set, including two kinds of situations:
1) there are the virtual point VP phases of the corresponding subregion of data object r in a dynamic subspace Skyline set
Deng；
2) there are data object r with respect to user's reference point quControl its virtual point VP for corresponding to subregion.
B) condition of step is to judge that current data object is in the step 3) that reversed subspace Skyline in Fig. 2 calculates
No is the reversed subspace Skyline object of back-reference point, and condition requires appointing in S1 in user's reference point subspace
Data object of anticipating " does not control " the global subspace Skyline of back-reference point partly in any dimension relative to back-reference point
Object.If condition is very, label is set in dynamic subspace Skyline data object, shows not to be mutual subspace
Skyline object.After S1 is identified as the Skyline object of non-mutual subspace, then do not go out in the test of next time
It is existing, the efficiency of test can be improved in this way.
In this way, the remaining object of all Skyline objects for being not identified as non-mutual subspace is mutual in set S1
The query result of subspace Skyline.
Particular embodiments described above has carried out further the purpose of the present invention, technical scheme and beneficial effects
It is described in detail, it should be understood that the above is only a specific embodiment of the present invention, the protection being not intended to limit the present invention
Range.It particularly points out, to those skilled in the art, all within the spirits and principles of the present invention, that is done any repairs
Change, equivalent replacement, improvement etc., should all be included in the protection scope of the present invention.
Claims (10)
1. a kind of parallel mutual subspace Skyline querying method, which is characterized in that the step of this method is as follows:
Step 1) establishes the B of an entitled BDi-tree according to the coordinate value of each dimension i to all data objects+Set rope
Draw, in order to according to the coordinate value of the far and near sequential access data object i-th dimension of Distance query object；
Step 2) is according to user's reference point quInitial position concurrently traverse BDi-tree index, traversal follows distance reference point
More closer, the synchronous principle of more preferential and each dimension；
Step 3) calculates the dynamic subspace Skyline of user's reference point, safeguards its object set S1, calculating process is using empty
Intend point VP to avoid redundancy from scanning；
Step 4) is according to back-reference point qrInitial position concurrently again traverse BDi-tree index, traversal strategies with it is above-mentioned
Step 2) it is identical；
Step 5) calculates the reversed subspace Skyline of back-reference point, safeguards object set S2, and calculating process is first demanded perfection police station
The Skyline object in space eliminates the data object of non-return subspace Skyline further according to trimming strategy；
The intersection of step 6) set of computations S1 and set S2 remove non-return subspace Skyline object that is, from set S1
Fall, obtains mutual subspace Skyline the results list of update.
2. a kind of parallel mutual subspace Skyline querying method according to claim 1, it is characterised in that: described
Step 2) in traversal strategies refer to access index interior joint sequencing and multiple dimensions access when how to control
Access stepping；Three kinds of situations of the strategy point consider:
1) in the same dimension, when the not visited left side node at a distance from query point than not visited right node
With more hour at a distance from query point, the node on the left side is first accessed, otherwise the node on access the right；
2) it in the same dimension, is saved when the node on the not visited left side is equal to not visited the right at a distance from query point
When point is at a distance from query point, the node of the right and left accesses respectively；
3) it in different dimensions, is accessed according to the far and near ascending order of not visited node and query point distance；Every time after access
Calculate the L1 distance of not visited node and query point；In all dimensions, have not visited node at a distance from query point most
Hour, the node in the dimension is first accessed, and is reached most in all dimensions at a distance from not visited node with query point
Until when big.
3. a kind of parallel mutual subspace Skyline querying method according to claim 1, it is characterised in that: described
Step 3) in calculating reference point quDynamic subspace Skyline the step of include:
1) according to references object quThe coordinate value q of dimension iuIn the initial access position of each dimension, i.e., [i] concurrently obtains it
With the coordinate value position on the immediate BDi-tree of qu [i] coordinate value；
2) a group access node is concurrently obtained according to index traversal strategies, and saved in lists, calculate the void of each dimension
Quasi- point VP；
3) for the current group node in list, the dynamic subspace Skyline of its part is calculated according to dynamic skyline method
Point；
4) it is concurrently counted on the dynamic subspace Skyline point of part with virtual point test and dynamic Skyline method
Dynamic subspace Skyline is calculated, safeguards the dynamic subspace Skyline set of reference point；
5) using the dynamic subspace Skyline point of part, concurrently judge reference point quDynamic subspace Skyline whether
Terminate；If meeting specified condition, reference point q is terminateduDynamic subspace Skyline calculate, obtain its results set
S1。
4. a kind of parallel mutual subspace Skyline querying method according to claim 1, it is characterised in that: described
Step 5) in calculating reference point qrReversed subspace Skyline the step of include:
1) according to back-reference object qrThe coordinate value q of dimension ir[i] concurrently obtains it in the initial access position of each dimension
And q it sets, i.e.,rCoordinate value position on the immediate BDi-tree of [i] coordinate value；
2) a group access node is concurrently obtained according to index traversal strategies, and be distributed in the list of each subregion, subregion root
It is obtained according to the relative positional relationship of reference point coordinate and current data point coordinate；
3) data object in each subregion is handled, back-reference point q is obtainedrReversed subspace in Skyline object.
5. a kind of parallel mutual subspace Skyline querying method according to claim 4, it is characterised in that: described
Data object in step 3) in each subregion of processing, obtains back-reference point qrReversed subspace in Skyline object,
Including the processing of four steps:
A) it is directed to the data object of each subregion, calculates its global subspace Skyline object；
B) for global subspace Skyline object, if it is only scanned once, pass through dynamic subspace
Object in Skyline set S1 judges whether it is reference point q according to specified conditionrReversed subspace in
Skyline object；
C) for global subspace Skyline object, if be scanned in all dimensions of whole subspaces once, eventually
Only reversed subspace Skyline calculates；
D) reference point q is safeguardedrReversed subspace in Skyline object, obtain its results set S2.
6. a kind of parallel mutual subspace Skyline querying method according to claim 1, it is characterised in that: described
Step 2) in user's reference point quWith the back-reference point q in step 4)rIt is the same data object, is in same height
In space.
7. a kind of parallel mutual subspace querying method according to claim 1, it is characterised in that: the step 2)
In user's reference point quWith the back-reference point q in step 4)rIt is different data object, in same sub-spaces.
8. a kind of parallel mutual subspace querying method according to claim 1, it is characterised in that: the step 2)
In user's reference point quWith the back-reference point q in step 4)rIt is different data object, in different subspaces.
9. a kind of parallel mutual subspace Skyline querying method according to claim 1 or 4, it is characterised in that: institute
Step 5) the conditional stated is the control of the object and virtual point VP tested in the dynamic subspace Skyline set currently obtained
Relationship, including two kinds of situations:
1) there are the virtual point VP of the corresponding subregion of data object r in a dynamic subspace Skyline set is equal；
2) there are data object r with respect to user's reference point quControl its virtual point VP for corresponding to subregion.
10. a kind of parallel mutual subspace Skyline querying method according to claim 5, it is characterised in that: described
Step 3) in the condition of b) step be: judge current data object whether be back-reference point reversed subspace Skyline pair
As condition requires the arbitrary data object in user's reference point subspace in S1 in any dimension relative to back-reference point
The not global subspace Skyline object of " half controls " back-reference point；If condition is true, the dynamic subspace
Label is set in Skyline data object, show be not mutual subspace Skyline object.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109947904A (en) * | 2019-03-22 | 2019-06-28 | 东北大学 | A kind of preference space S kyline inquiry processing method based on Spark environment |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103778194A (en) * | 2014-01-07 | 2014-05-07 | 浙江大学 | Commodity recommendation method based on reverse skyline zone |
| US20150213125A1 (en) * | 2014-01-28 | 2015-07-30 | Snu R&Db Foundation | System and method for skyline queries |
| CN106777091A (en) * | 2016-12-14 | 2017-05-31 | 大连大学 | The double filtering searching systems of the Skyline based on many medical factors under mobile O2O environment |
| CN108052514A (en) * | 2017-10-12 | 2018-05-18 | 南京航空航天大学 | A kind of blending space Indexing Mechanism for handling geographical text Skyline inquiries |
-
2018
- 2018-11-13 CN CN201811346389.XA patent/CN109446294B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103778194A (en) * | 2014-01-07 | 2014-05-07 | 浙江大学 | Commodity recommendation method based on reverse skyline zone |
| US20150213125A1 (en) * | 2014-01-28 | 2015-07-30 | Snu R&Db Foundation | System and method for skyline queries |
| CN106777091A (en) * | 2016-12-14 | 2017-05-31 | 大连大学 | The double filtering searching systems of the Skyline based on many medical factors under mobile O2O environment |
| CN108052514A (en) * | 2017-10-12 | 2018-05-18 | 南京航空航天大学 | A kind of blending space Indexing Mechanism for handling geographical text Skyline inquiries |
Non-Patent Citations (1)
| Title |
|---|
| 蒋涛 等: "排序的相互k-Skyband 查询算法", 《软件学报》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109947904A (en) * | 2019-03-22 | 2019-06-28 | 东北大学 | A kind of preference space S kyline inquiry processing method based on Spark environment |
| CN109947904B (en) * | 2019-03-22 | 2021-07-30 | 东北大学 | Preference space Skyline query processing method based on Spark environment |
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