Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
236 words
A method of selecting an optimal plan (60) for solving a problem (10) in a computerized database system (100) having a plurality of computer resources (102, 104, 106, 108) that can operate in parallel, the method comprising: a. dividing the problem (10) into a plurality of sub-problems (10, 11, 12, 13, 15, 17, 19); b. arranging the sub-problems (10, 11, 12, 13, 15, 17, 19) hierarchically in a plurality of levels (1, 2, 3), each sub-problem (11, 12, 13) in a first level (1) requiring that data be retrieved from a storage resource (106, 108) and each sub-problem (10, 15, 17, 19) in a higher level (2, 3) requiring that a result from a sub-problem (11, 12, 13) in a lower level (1) be manipulated in a computation resource (102, 104); c. identifying all sub-plans (20, 22, 50, 52) that could be used to solve each sub-problem (11, 15); d. deleting, from among the sub-plans (20, 22) associated with any sub-problem (11) in the first level having more than one sub-plan, any sub-plan (22) that requires more time from each of a plurality of the computer resources (102, 106) than is required by another sub-plan (20) in solving the same sub-problem; e. computing a response time for each possible combination of the remaining sub-plans (20) that would solve the problem; and f. selecting that combination which has the lowest response time as the optimal plan (60).
Claim 2
Dependent Claim
42 words
A method for selecting an optimal plan (60) as recited in claim 1, the step (d) comprising the step of: d1. repeating step (d) hierarchically to every level (2, 3) higher than the first level (1) of the sub-problems (11, 12, 13).
Claim 3
Dependent Claim
120 words
A method for selecting an optimal plan (60) as recited in claim 2, the step (b) comprising the step of: b1. retrieving a result from a sub-problem (13) in a first level (1) and a result from a sub-problem (15) in the immediate lower level (2) far each sub-problem (10) in a level other than the first level (1); and the step (d1) comprising the step of: d2. requiring, for each sub-plan (30) associated with a sub-problem (10) in a level other than the first level (1), that a result from a sub-problem (15) in the immediate lower level (2) and a result from a sub-problem (13) in the first level (1) to be manipulated in a computation resource (102).
Claim 4
Dependent Claim
22 words
A method for selecting an optimal plan as recited in claim 3, wherein the data in step (b) comprise tables of information.
Claim 5
Dependent Claim
19 words
A method for selecting an optimal plan as recited in claim 4, wherein the problem comprises a select-project-join query.
Claim 6
Dependent Claim
85 words
A method for selecting an optimal plan as recited in claim 2, the step (b) comprising the step of: b1. retrieving results from two lower-level sub-problems (71, 72) for each sub-problem (70) in a level other than the first level (1); and the step (d1) comprising the step of: d2. requiring, for each sub-plan (80) associated to a level (4) other than the first level (1) of the sub-problem, that results from two lower-level sub-problems (72, 71) to be manipulated in a computation resource (104).
Claim 7
Dependent Claim
22 words
A method for selecting an optimal plan as recited in claim 6, wherein the data in step (b) are tables of information.
Claim 8
Dependent Claim
19 words
A method for selecting an optimal plan as recited in claim 7, wherein the problem is a select-project-join query.
Claim 9
Dependent Claim
86 words
A method for selecting an optimal plan as recited in claim 2, the step (c) comprising the steps of: c1. calculating the total computing time that the system needs to solve the problem with the system performing minimal amount of work; c2. establishing a factor indicating the maximum throughput that the system may be allowed to degrade; and the step (d) comprising the step of: d1. deleting any sub-plans requiring more time to solve than the product of the calculated total computing time and the factor.
Claim 10
Dependent Claim
133 words
A method for selecting an optimal plan as recited in claim 2, the steps (c) comprising the step of: c1. calculating the response time T₀ that the system needs to solve the problem with the system performing minimal amount of work; c2. calculating the total computing time W₀ that the system needs to solve the problem with the system performing minimal amount of work; c2. establishing a factor indicating the maximum amount of extra work required to reduce the response time; the step (d) comprising the steps of: d1. calculating, for every sub-plan, the response time T p and the total computing time W p that the system needs to solve the problem with the sub-plan; and d2. deleting every sub-plan If (T₀ - T p )/(W p - W₀) < the factor.