Expansion of database search queries

1. A method comprising:

executing instructions stored on a machine-readable medium readable by a processor which when executed cause the processor to perform operations comprising:

receiving a search query including a token, the search query to be performed on data in a database stored on the machine-readable medium or a different machine-readable medium, the database including items of data that are represented by data strings;

determining a synonym candidate for the token;

adding the synonym candidate as a synonym for the token into an expansion dictionary in response to a determination that the number of data strings having the synonym candidate exceeds a threshold and a determination that the synonym candidate and the token are in a same category for a level of a tree hierarchy in the database, the tree hierarchy including a plurality of nodes having parent-child relationships;

expanding the search query to include the synonym to form an expanded search query; and

performing a search, using the expanded search query, for data in the database.

2. The method of claim 1 , wherein the operations comprise:

receiving a search query having the token for data in the database from a requester; and

returning a result of the search to the requester.

3. The method of claim 2 , wherein the operations comprise:

returning the expanded search query to the requester; and

receiving an approval of the expanded search query from the requester, prior to performing the search using the expanded search query.

4. The method of claim 1 , wherein adding the synonym candidate as the synonym for the token into the expansion dictionary is in response to a determination that a number of search queries into the database having the synonym candidate exceeds a threshold.

5. The method of claim 1 , wherein determining the synonym candidate for the token comprises determining a different form of the token based on a role in a sentence for the different form in comparison to the role of the token in the sentence.

6. The method of claim 1 , wherein determining the synonym candidate for the token comprises determining a plural form of a singular form of the token.

7. The method of claim 1 , wherein the threshold is 15.

8. A machine-readable medium including instructions, which when executed by a machine cause the machine to perform operations comprising:

receiving a search query including a token, the search query to be performed on data in a database stored on the machine-readable medium or a different machine-readable medium, the database including items of data that are represented by data strings;

determining a synonym candidate for the token;

adding the synonym candidate as a synonym for the token into an expansion dictionary in response to a determination that the number of data strings having the synonym candidate exceeds a threshold and a determination that the synonym candidate and the token are in a same category for a level of a tree hierarchy in the database, the tree hierarchy including a plurality of nodes having parent-child relationships;

expanding the search query to include the synonym to form an expanded search query; and

performing a search, using the expanded search query, for data in the database.

9. The machine-readable medium of claim 8 , further comprising:

receiving a search query having the token for data in the database from a requester; and

returning a result of the search to the requester.

10. The machine-readable medium of claim 9 , further comprising:

returning the expanded search query to the requester; and

receiving an approval of the expanded search query from the requester, prior to performing the search using the expanded search query.

11. The machine-readable medium of claim 8 , wherein adding the synonym candidate as the synonym for the token into the expansion dictionary is in response to a determination that a number of search queries into the database having the synonym candidate exceeds a threshold.

12. The machine-readable medium of claim 8 , wherein determining the synonym candidate for the token comprises determining a different form of the token based on a role in a sentence for the different form in comparison to the role of the token in the sentence.

13. The machine-readable medium of claim 8 , wherein determining the synonym candidate for the token comprises determining a plural form of a singular form of the token.

14. The machine-readable medium of claim 8 , wherein the threshold is 15.