Comparatively crawling web page data records relative to a template

1. A method of searching data records on a web page, the method comprising:

storing, in a memory, instructions for performing the method of searching data records on a web page;

executing the instructions on a processor;

according to the instructions being executed:

receiving data records selected by a user from a displayed web page;

defining a web block based on the data records that were selected by the user, wherein the web block represents search criteria to be used to identify a similar web block of data records on another web page;

generating a structure template based on the defined web block, wherein the structure template represents an underlying schema of the web block;

comparing the generated structure template to a structure of other data records displayed on another web page; and

determining if the structure of the other data records matches the generated template, wherein the determining if other data records match the generated template comprises calculating a minimum difference using an equation,

Diff

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T

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T

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=

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T

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wherein:

the generated template, T is a Document Object Model (DOM) tree template based on the defined web block;

T′ is a DOM tree of the other data records;

n(T) is a number of nodes in T;

n(T′) is a number of nodes in T′;

m is a number of pairs of corresponding sub-trees in T and T′;

Spi is a sub-tree of T;

Spi′ is a sub-tree of T′;

n(Spi) is a number of nodes in Spi; and

n(Spi′) is a number of nodes in Spi′

Diff (T, T″) is recursively defined to be the edit distance between T and T′;

Diff(S pi , S′ pi ′) is recursively defined to be the edit distance between S pi and S′ pi ′.

2. The method of claim 1 , wherein the defining a web block comprises incorporating the received data records into a Document Object Model (DOM) tree structure.

3. The method of claim 1 , wherein the web page comprises hypertext mark-up language.

4. The method of claim 1 , wherein the first DOM tree is associated with the generated template and the second DOM tree is associated with the other data records.

5. A computer-readable storage medium encoded with computer-executable instructions that, when executed, direct a computing system to perform a method, the method comprising:

receiving data records selected from a displayed web page, the received data records including a user's selection of the data records;

defining a web block based on the received data records that were selected by the user, wherein the web block represents search criteria to be used to identify a similar web block of data records on another web page;

generating a structure template based on the defined web block, wherein the structure template represents an underlying schema of the web block; and

extracting a structure of other data records from the web page based on the generated template, wherein the extracting the other data records from the web page comprises calculating a minimum difference using the equation

Diff

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Diff

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,

wherein:

T is a Document Object Model (DOM) tree template based on the defined web block;

T′ is a DOM tree of the other data records;

n(T) is a number of nodes in T;

n(T′) is a number of nodes in T′;

m is a number of pairs of corresponding sub-trees in T and T′;

Spi is a sub-tree of T;

Spi′ is a sub-tree of T′;

n(Spi) is a number of nodes in Spi; and

n(Spi′) is a number of nodes in Spi′

Diff (T, T″) is recursively defined to be the edit distance between T and T′;

Diff(S pi , S′ pi ′) is recursively defined to be the edit distance between S pi and S′ pi ′.

6. The computer-readable storage medium of claim 5 , wherein the defining a web block comprises incorporating the received data records into a first Document Object Model (DOM) tree structure.

7. The computer-readable storage medium of claim 5 , wherein the method further comprises a learning process to learn features of an underlying schema of the defined web block.

8. A method of interactively crawling a web page, the method comprising:

storing, in a memory, instructions for performing the method of interactively crawling a web page;

executing the instructions on a processor;

according to the instructions being executed:

defining a web block based on a plurality of data records selected by a user from a displayed web page, wherein the web block represents search criteria to be used to identify a similar web block of data records on another web page;

generating a structure template based on the defined web block, wherein the structure template represents an underlying schema of the web block;

comparing the generated structure template to a structure of other information displayed on the web page; and

determining if the structure of the other data records match the generated template, wherein the determining if other data records match the generated template comprises calculating a minimum difference using an equation,

Diff

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(

T

,

T

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=

n

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T

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+

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-

Diff

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(

S

pi

,

S

pi

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.

)

wherein:

the generated template, T is a Document Object Model (DOM) tree template based on the defined web block;

T′ is a DOM tree of the other data records;

n(T) is a number of nodes in T;

n(T′) is a number of nodes in T′;

m is a number of pairs of corresponding sub-trees in T and T′;

Spi is a sub-tree of T;

Spi′ is a sub-tree of T′;

n(Spi) is a number of nodes in Spi; and

n(Spi′) is a number of nodes in Spi′

Diff (T, T″) is recursively defined to be the edit distance between T and T′;

Diff(S pi , S′ pi ′) is recursively defined to be the edit distance between S pi and S pi ′.

9. The method of claim 8 , wherein the defining a web block comprises incorporating data included in the web block into a Document Object Model (DOM) tree structure.

10. The method of claim 8 , wherein the first DOM tree is associated with the generated template.

11. The method of claim 8 , wherein the second DOM tree is associated with the other data records.