Rule-based transformation of metadata

• US 20050154695A1
• Filed: 01/09/2004
• Published: 07/14/2005
• Est. Priority Date: 01/09/2004
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Oracle International Corporation (Oracle Corporation)
• Inventors: Gonzalez, Zandro Luis, Zhang, Xiaoge
• Granted Patent: US 8,738,663 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/217 Database tuning G06F16/2282 takes precedence; database performance monitoring G06F11/3409

Abstract

A computer automatically reads each object in a metadata that is descriptive of a database. Then the computer automatically applies a number of rules, to check if the object triggers a rule. If so, then the computer automatically changes the metadata as per an action identified by the triggered rule. After all rules are applied to the object, and after all objects in the metadata are processed, the resulting metadata is used to change the database'"'"'s structure. The objects may be read from the metadata in an order (e.g. hierarchy) specified in meta-metadata that is descriptive of the metadata.

Claims

1. A method performed in a programmed computer, for changing a database, the method comprising:

automatically reading an object in metadata descriptive of a structure of the database;

automatically checking if the object triggers a rule from among a predetermined set of rules; and

automatically changing the metadata in accordance with an action associated with the rule, if the rule is triggered by the object.

wherein said acts of automatically reading, automatically checking and automatically changing are repeatedly performed, once for each object in the metadata.

2. The method of claim 1 further comprising:

automatically selecting each object for reading from among the plurality of objects in the metadata, in a specific order that is inherent in meta-metadata, the meta-metadata being descriptive of a structure of the metadata.

3. The method of claim 2 wherein:

the meta-metadata has a tree structure; and

the meta-metadata comprises relationships between various types of objects in the metadata.

4. The method of claim 3 wherein:

the database has a plurality of tables, each table has at least one column; and

the specific order comprises selecting a table object in the metadata for reading before a column object owned by said table object.

5. The method of claim 2 wherein:

said automatically selecting comprises using a first stack to temporarily store object types read from the meta-metadata, and using a second stack to temporarily store objects read from the metadata.

6. The method of claim 5 wherein:

said first stack and said second stack are processed symmetrically.

7. The method of claim 1 further comprising writing the object, wherein:

each rule in the predetermined set is one of a kind selected from a group consisting of;

(a) pre-trigger specifying performance of the action before writing the object (b) post-trigger specifying performance of the action after writing the object and (c) pre-post trigger specifying performance of one portion of the action before writing the object and another portion of the action after writing the object.

8. The method of claim 1 wherein:

each rule in the predetermined set has a priority; and

said priority is used in selecting a rule for application to the object during automatically checking.

9. The method of claim 1 wherein the automatically changing comprises changing an attribute of the object.

10. The method of claim 1 wherein the automatically changing is performed on metadata in said database, and the method does not write to said database if no rule is triggered during automatically checking.

11. The method of claim 1 wherein the automatically changing is performed on metadata in another resource that is different from said database, and the method further comprises:

leaving the metadata in said another resource unchanged if no rule is triggered by the object.

12. The method of claim 1 further comprising:

automatically modifying the structure of the database to conform to metadata resulting from performance of a plurality of acts of automatically changing, after all objects in the metadata are checked against the predetermined set of rules.

13. The method of claim 1 further comprising:

automatically creating a new database in conformance with metadata resulting from repeated acts of automatically changing.

14. A carrier wave encoded with instructions to perform the method of claim 1.

15. A computer readable storage medium encoded with instructions to perform the method of claim 1.

16. A computer comprising a processor and a memory coupled to the processor, the memory being encoded with metadata descriptive of a structure of the database, the memory being further encoded with a predetermined set of rules to be applied to a plurality of objects in the metadata, the memory being further encoded with instructions to:

automatically read each object in the metadata;

automatically apply at least one rule from the predetermined set, to check if said each object triggers the rule; and

automatically change the metadata in accordance with an action specified in the rule, if the rule is triggered by said each object.

17. An apparatus for changing a database in a computer, the apparatus comprising:

means for automatically reading each object in a plurality of objects in metadata descriptive of a structure of the database;

means for automatically checking if at least one rule from among a predetermined set of rules is triggered by an object that is read by the means for automatically reading; and

means for automatically changing the metadata in accordance with an action associated with the rule, if the means for automatically checking indicates that the rule is triggered by the object.