Method for converting relational data into a structured document

Claim 3

The method according to claim 1 , wherein the user query is in XML-QL.

Claim 4

The method according to claim 2 , wherein the view query is a RXL query.

Claim 5

The method according to claim 3 , wherein the executable query is another RXL query.

Claim 6

The method device according to claim 1 , wherein said step of receiving the user query includes receiving the user query from an application over a distributed network.

Claim 7

The method according to claim 5 , wherein the distributed network is a private network.

Claim 8

The method according to claim 5 , wherein the distributed network is the World Wide Web.

Claim 9

The method according to claim 5 , further including the step of transmitting the structured document to the application over the distributed network.

Claim 10

The method according to claim 1 , wherein an answer to the executable query includes a fragment of the relational database.

Claim 11

The method according to claim 9 , wherein the fragment is one data item or a set of data items.

Claim 12

The method according to claim 9 , wherein the fragment is an aggregate value.

Claim 13

The method according to claim 9 , wherein the structured document includes the answer to the executable query.

Claim 14

The method according to claim 1 , wherein the data extraction portion includes at least one SQL query.

Claim 15

The method according to claim 13 , wherein the construction portion is an XML template.

Claim 16

The method according to claim 13 , wherein said step of receiving the at least one tuple stream includes receiving one tuple stream for each SQL-query included in the data extraction portion.

Claim 17

The method according to claim 1 , wherein said step of forming the executable query includes combining fragments of the user query and the view query.

Claim 18

A computer readable medium including a set of executable instructions stored thereon for converting relational data stored in a relational database into structured document data, the set of instructions including: forming an executable query from a view query that defines a structured document view of the relational database and a user query, a structure of the view query being independent from a structure of the relational data in the relational database; partitioning the executable query into a data extraction portion and a construction portion; retrieving at least one tuple stream from the relational database according to the data extraction portion; and merging the at least one tuple stream and the construction portion to generate a structured document, wherein the structured document view is capable of defining a document of arbitrary nesting depth.

Claim 19

A computer readable medium including a set of executable instructions stored thereon for converting relational data stored in a relational database into structured document data, the set of instructions including: forming an executable query from a view query that defines a structured document view of the relational database and a user query, a structure of the view query being independent from a structure of the relational data in the relational database; partitioning the executable query into a data extraction portion and a construction portion; retrieving at least one tuple stream from the relational database according to the data extraction portion; and merging the at least one tuple stream and the construction portion to generate a structured document, wherein the structured document view is capable of defining a document of arbitrary nesting depth.

Claim 20

The computer readable medium according to claim 17 , further comprising storage for the view query.

Claim 21

The computer readable medium according to claim 18 , wherein the view query is a RXL query.

Claim 22

The computer readable medium according to claim 19 , wherein the executable query is another RXL query.

Claim 23

The computer readable medium according to claim 17 , wherein an answer to the executable query includes a fragment of the relational database.

Claim 24

The computer readable medium according to claim 21 , wherein the fragment is one data item or a set of data items.

Claim 25

The computer readable medium according to claim 21 , wherein the fragment is an aggregate value.

Claim 26

The computer readable medium according to claim 21 , wherein the structured document includes the answer to the executable query.

Claim 27

The computer readable medium according to claim 17 , wherein the data extraction portion includes at least one SQL query.

Claim 28

The computer readable medium according to claim 25 , wherein said step of retrieving the at least one tuple stream includes retrieving one tuple stream for each SQL-query included in the data extraction portion.

Claim 29

The computer readable medium according to claim 17 , wherein said instruction of forming the executable query includes combining fragments of the user query and the view query.

Claim 30

A computer system for converting relational data in a relational database into structured document data, said system comprising: a query composer module configured to form an executable query from a view query that defines a structured document view of the relational data and a user query, the view query having a structure that is independent of a structure of the relational data in the relational database; a translator module coupled to the query composer module configured to receive the executable query, partition the executable query into a data extraction portion and an construction portion, and transmit the data extraction portion to a relational database; a generator module configured to receive the construction portion from said translator module, receive at least one tuple stream from the relational database based on data extraction portion, and merge the at least one tuple stream and the construction portion to generate a structured document, wherein the structured document view is capable of defining a document of arbitrary nesting depth.

Claim 31

A computer system for converting relational data in a relational database into structured document data, said system comprising: a query composer module configured to form an executable query from a view query that defines a structured document view of the relational data and a user query, the view query having a structure that is independent of a structure of the relational data in the relational database; a translator module coupled to the query composer module configured to receive the executable query, partition the executable query into a data extraction portion and an construction portion, and transmit the data extraction portion to a relational database; a generator module configured to receive the construction portion from said translator module, receive at least one tuple stream from the relational database based on data extraction portion, and merge the at least one tuple stream and the construction portion to generate a structured document, wherein the structured document view is capable of defining a document of arbitrary nesting depth.

Claim 32

The computer system according to claim 28 , wherein said translator module receives a description of a schema of the relational data prior to partitioning the executable query.

Claim 33

The computer system according to claim 28 , wherein the user query is in XML-QL, the view query is a RXL query and the executable query is another RXL query.

Claim 34

The computer system according to claim 28 , wherein said query composer module is configured to receive the user query from an application over a distributed network.

Claim 35

The computer system according to claim 31 , wherein said generator module is configured to transmit the structured document to the application over the distributed network.

Claim 36

The computer system according to claim 28 , wherein an answer to the executable query includes a fragment of the relational database.

Claim 37

The computer system according to claim 33 , wherein the fragment is one data item, a set of data items or an aggregate value.

Claim 38

The computer system according to claim 33 , wherein the structured document includes the answer to the executable query.

Claim 39

The computer system according to claim 28 , wherein the data extraction portion includes at least one SQL query.

Claim 40

The computer system according to claim 36 , wherein said generator module receives one tuple stream for each SQL-query included in the data extraction portion.

Claim 41

The computer system according to claim 28 , wherein said query composer module combines fragments of the user query and the view query to form the executable query.

Claim 42

The computer system according to claim 28 , wherein the data extraction portion is executable by the relational database.

Claim 43

The computer system according to claim 28 , where in the query composer module includes a pattern matcher module configured to match patterns of the user query and the view query to obtain a solutions relation, in which each tuple represents a match; and a rewriter module configured to rewrite each tuple.

Claim 46

The method according to claim 41 , wherein the transformation language is RXL.

Claim 47

The method according to claim 41 , wherein said step of composing includes the steps of: matching patterns of the user query and the view query to obtain a solutions relation, in which each tuple represents a match; and rewriting each tuple into a clause in the transformation language.

Claim 48

The method according to claim 43 , wherein said step, of matching patterns includes the steps of: constructing a view tree from the view query; and evaluating the user query on the view tree.

Claim 49

The method according to claim 43 , wherein said step of rewriting includes the step of constructing at least one block using from and where clause of the view query and a construct clause of the user query.

Claim 50

The method according to claim 43 , wherein said step of rewriting each tuple into a clause in the transformation language is conducted on the basis of from/where clauses of the view query, the solutions relation, and construct clauses of the user query.

Claim 51

The method according to claim 1 , wherein a format of the structured document is XML.

Claim 52

The computer readable medium according to claim 17 , wherein a format of the structured document is XML.

Claim 53

The computer system according to claim 28 , wherein a format of the structured document generated by the generator module is XML.