Abstract:
A system and method is provided wherein a user chooses from an allowed preselected domain of query element values, presenting a query comprising a plurality of selected query element values, which form the basis for indexing query results. A database lookup is done according to the user&#39;s selections and index values, as well as relevancy values of other members of the allowed preselected domain of query element values. In some embodiments the query results are assigned to arbitrary tags or numbers to prevent unauthorized competing search providers from appropriating the query results.

Description:
RELATED APPLICATIONS  
       [0001]    The present application claims the benefit, under 35 U.S.C. §119(e), of U.S. Provisional Application Serial No. 60/230,354, filed Sep. 6, 2000, and entitled “System and Method for Processing Database Queries” which is hereby incorporated by reference. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The field of the invention relates generally to databases, and more particularly to processing database queries.  
         BACKGROUND  
         [0003]    Computer systems having databases are generally used to store and obtain information. These computer systems may be stand-alone computers that serve one or more users, or the systems may be networked to provide access to a database from multiple systems referred to as clients. These database systems carry out communication with clients through one or more communication protocols, as is known in the art. For example, these database and clients may communicate over a network, such as the Internet, using the well-known TCP/IP protocol. The client systems may interact with the database using one or more application programs such as an Internet browser which accepts input from a user and display information received from database systems. The database may be, for example, a relational database which stores character, binary, or other data format that may be searched and retrieved.  
           [0004]    Database access has become standard for supporting operations performed on networks such as the Internet. For example, databases are used to support searching, by providing a resource which stores links to data resources and to other databases. For example, databases are used to classify and store links, called Uniform Resource Locators (URLs) that serve as addresses to resources such as Web sites, audio/video files, and other types of media. These addresses are provided by database systems in response to queries submitted to the database systems through interfaces to the database systems displayed in browser applications. These database systems are sometimes referred to as search engines, and may be used as a part of a directory service, company&#39;s Web site, or any other method for searching and retrieving information.  
           [0005]    Interfaces for databases generally include a text entry field, wherein a user may enter one or more keywords associated with what he or she is searching for. These keywords are processed by the database system, and a set of results is displayed to the user. The user then reviews these results to determine how pertinent the results are to what he or she is looking for. These databases function as a directory services for resources on the Internet. Examples of such searching systems include Yahoo! (www.yahoo.com), Google (www.google.com), and others. Yahoo! and other search engines generally provide two methods for finding information. First, a directory method, which provides pathways for navigating through content related by a logical relationship. The second method is a key word search. Some services such as Yahoo! utilize the catalog information provided by other services such as Google for performing the search.  
           [0006]    One main problem with existing systems that use the directory search method is that a user must navigate hierarchical directory structures. Taking a “wrong” or a non-ideal “turn” in the search path, by selecting a branch in the search which leads away from the best result, will significantly degrade the final outcome of the user&#39;s search.  
           [0007]    Keyword search systems generally accept keyword entry and display a number of results, the results being ordered based upon the frequency of the keyword appearing in the resource, or some other ranking criteria. The database systems perform preprocessing on the resources by indexing data of the resources by keywords. This involves analyzing Internet resources with programs referred to as Web spiders or crawlers which visit Internet links and perform keyword processing on resource content associated with the link, generally involving millions of processed resources. Furthermore, a perplexingly large number of search results is typically returned by such keyword search engines. Thousands of search results are usually presented to the user, and the sorting of the search results can involve errors due to the automated indexing of the search results or the difficulties described above.  
           [0008]    Further, more simple keyword association and relevancy also produce irrelevant results sometimes. When documents are retrieved based upon a keyword search, resources such as documents having those combination of keywords are retrieved, even though the documents&#39; content may not be relevant. A user must evaluate individually each link to determine whether an indicated document is relevant. Also, the number of records produced is generally large, and a query retrieving thousands of records is not uncommon. Retrieving large number of records is problematic to a user, as the process of reviewing each link is tedious and time-consuming for the user and requires excessive computational resources.  
           [0009]    Keywords and other natural language (NL) inputs are generally processed by the system as shown in FIG. 1, which shows a conventional NL searching system  10 . Natural language searches generally begin with a user  100  entering an unstructured query  102  into an interface associated with the database search system. A NL query preprocessor  104  processes the unstructured query  102  to determine the meaning of the query. This meaning is formulated into predetermined search criteria  106 , which are provided to a query keyword parser  108 , which associates meaning for each of the keywords, and may expand the query by generating similar terms for one or more keywords. The unstructured query  102  is also passed directly to the query keyword parser  108  that processes the unstructured query  102  to determine keywords and logical operators  110  connecting those keywords. For example, an input query of “map and Massachusetts” might produce, by the query keyword parser  108 , the keywords “map” and “Massachusetts” with a logical operator “and.” The NL query preprocessor  104  may also determine that the user wants driving directions for Massachusetts, or to retrieve maps of major metropolitan areas, based on the meaning of the phrase “map and Massachusetts.” 
           [0010]    A database  150  is indexed by keywords in this case, and those keywords and logical operators are compared to that of the keyword index to produce a (typically large) number of search results  118 . These search results  118  are presented to the user  100  by a query result presenter  120 , within a graphical user interface, and are generally ranked by relating the keywords to the database entries.  
           [0011]    As discussed above, search engines may include a NL query preprocessor  104  which attributes some meaning to the terms. For instance, this may be performed through analyzing lexical semantics which determines the meanings of each of the keywords, and by analyzing compositional semantics which is the knowledge of how keywords are combined to form larger meanings. In general, morphology is the study of the meaningful components of words, while syntax is the study of the relationship between words. There are also many other ways to analyze natural language. For example, semantics is the study of meaning, pragmatics is the study of how language is used to accomplish goals, and discourse is the study of linguistic units larger than a single utterance.  
           [0012]    Because meaning may be attributed to a query at many levels, NL processing is a complex process which involves complex algorithms. Further, these algorithms are not perfect; there are frequent ambiguities in natural language interpretation. Because of these ambiguities, and because of the inherently subjective nature of database queries, NL processing of input queries yields imperfect search results. Natural language processing is more fully described in the book entitled “Natural Language Understanding” by James Allen, 2nd edition (January 1995), Addison-Wesley Publishing Co., which is hereby incorporated by reference.  
           [0013]    As discussed, there are many drawbacks of implementing NL in association with database searching. For example, the user may pose a question, and the question is not interpreted properly, yielding incorrect results. The user may need to restructure the question in a different manner to obtain meaningful results.  
           [0014]    There are sites that implement NL analysis such as the portal AskJeeves (www.askjeeves.com), which ascribes meaning to input queries by matching a user&#39;s question to a question that was previously defined. This portal allows a user to pose questions in a NL format, and retrieves the most relevant question based on a keyword analysis. However, as discussed above, natural language analysis produces ambiguous results and is complicated to perform. Thus, AskJeeves, and others, do not generally perform a perfect match. Further, questions posed to the system by a user do not necessarily have a corresponding question predefined in the system. Also, sample questions presented to the user in response to a query are usually not relevant. Because AskJeeves is linked to a keyword indexed database, the results returned must be processed by the user, and the AskJeeves system produces the same volume of information as standard keyword matching search engines.  
           [0015]    Many database search engines also, in addition to keyword-based and NL-based search functions, provide a hierarchical listing of information to compliment these functions. This hierarchical listing is a categorization of links, usually programmed manually and take the form of directories. When new links are added, they are generally placed within the predetermined hierarchy or directory tree. As described earlier, navigating through a directory tree requires a user to accurately choose the best choice from a plurality of presented choices. The presented choices may themselves not include a choice corresponding to a path leading to the information the user actually desires to find. Making a non-ideal selection or being presented with selections none of which are ideal, forces a user down a search path that will not lead to the desired results. Also, excessively long search paths involving many user selections are generally required to reach the end point of a search. No logical relationship necessarily exists between members of a directory level or members of different directory levels. These difficulties cause directory-based search engines or navigators to be an inefficient means for retrieving information.  
         SUMMARY  
         [0016]    According to one embodiment of the invention, a system and method is provided wherein common elements of questions, or “queries”, are used to assist users in constructing their questions. In particular, users select a “query element” value from a list of allowed values, or a “domain,” of each query element. Instead of using keywords and determining their relevancy to elements in a database, user-selected values of query elements of a query are used to retrieve indexed results from the database system. The database system may be, for example, a relational classification system. Information may be stored in the database by classifying the information by assigning, for an information object of the database, a number of values for each query element. Also, a relevancy index may be assigned among the allowed values of a query element, if multiple values of a query element are possible. According to one aspect of the invention, the query submitted by a user is restricted to one of a plurality of predefined formats and allowed values, and the predefined formats and allowed values are associated with database information objects.  
           [0017]    Because it is the user&#39;s responsibility to properly phrase a query or search criteria in a text-free format, conventional systems perform only as good as the input provided by the user. According to various embodiments of the present invention, the query response information is provided in a non-hierarchical format, such that the user does not need to traverse directories or hierarchies to find the requested information.  
           [0018]    Further, the amount of calculation carried out by the server to respond to a query and retrieve information is often far less than that required by standard keyword-parsing and NL-processing systems. Additionally, the database needed to store the information is reduced.  
           [0019]    Some embodiments call for a human or a machine “editor” to sort and assign relevance values to query element values. This way an optimized first-time query brings up only the most relevant database search results.  
           [0020]    Also, Internet links may be represented by arbitrary numbers, or codes, to prevent other Internet services from directly copying the search results. That is, to hide content from other Internet services, results such as links that are returned to the user are assigned arbitrary numbers used by the system to refer to the actual links.  
           [0021]    Additionally, state information may be associated with the links and maintained by the server. In this way outdated links could be tracked and the system can determine the last date a link was checked, or whether a link was found valid, invalid, or had any other condition worthy of reporting. Accordingly, some embodiments of the invention are directed to:  
           [0022]    A method for processing database queries, comprising: presenting, to a user, a plurality of query elements, each query element having a plurality of allowed query element values; receiving, from the user, a plurality of selected query element values, each selected query element value corresponding to a respective query element, wherein the value of each selected query elements is selected by the user from the respective plurality of allowed query element values corresponding to the respective query elements; indexing a database by forming an index from the selected query element values; and retrieving, from the database, information objects corresponding to the index.  
           [0023]    A system for processing a database query, comprising: a server; a client coupled to the server through a network; a database coupled to the server, the database comprising information objects; a user interface running on the client for presenting query results to a user; a selector, implemented in the user interface, for allowing the user to select a plurality of selected query element values from respective pluralities of allowed query element values for respective query elements; and an indexer for forming an index to the database, using the selected query element values. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0024]    [0024]FIG. 1 shows a block diagram of a conventional NL search engine.  
         [0025]    [0025]FIG. 2 shows a general purpose client-server computer system upon which various embodiments of the invention may be practiced.  
         [0026]    [0026]FIG. 3 shows an exemplary user interface in accordance with one embodiment of the invention.  
         [0027]    [0027]FIG. 4 shows two exemplary query elements and allowed query element values and selected query element values which can be selected using the selector.  
         [0028]    [0028]FIG. 5 shows a block diagram of a search system in accordance with one embodiment of the invention.  
         [0029]    [0029]FIG. 6 shows a logical data model that may be implemented in the system shown in FIG. 3.  
         [0030]    [0030]FIG. 7 shows a table mapping link information, the table being maintained by a search system. 
     
    
     DETAILED DESCRIPTION  
       [0031]    The present invention will be more completely understood through the following description, which should be read in conjunction with the accompanying drawings, in which similar reference numbers indicate similar structures.  
         [0032]    [0032]FIG. 2 shows a computer system  20  suitable for implementing various embodiments of the present invention. One or more client systems  209 A-B communicate with one or more server systems  210 A-B for the purposes of exchanging information and performing transactions, such as database transactions. These systems communicate using a communication protocol over a network  200 . Server  210  may be, for example, a hypertext transfer protocol (HTTP) server that is configured to perform database transactions. The servers  210  may accept and process search queries received from a user. In particular, a user may provide and receive, respectively, input/output through an interface of a client  209  system. The query information is transferred over the network  200  and stored and processed at one or more servers  210  using one or more communication protocols, such as TCP/IP and one or more transfer protocols such as HTTP. Other protocols are available as known or as becomes known to those skilled in the art.  
         [0033]    The communication network  200  may be an Ethernet network, Fast Ethernet or other type of local or wide area network (LAN or WAN), a point-to-point network provided by telephone services, or other type of communication network or combination of networks. Information consumers and providers, also referred to in the art as client and server systems, respectively, communicate through the network  200  to exchange information.  
         [0034]    Computer system  201  may include a processor  202  connected to one or more storage devices  203 , such as a disk drive, through a communication device, such as a bus  207 . The computer system  201  may also include one or more output devices  204 , such as a monitor, printer, or graphic display, or printing device and one or more input devices  208  such as a keyboard, mouse or other device. The computer system  201  typically includes a memory  205  for storing programs and data during operation of the computer system  201 . In addition, the computer system may contain one or more communication devices  206  that connect the computer system  201  to the communication network  200 .  
         [0035]    Computer system  201  may be a general purpose computer system that is programmable using a high-level computer programming language. The computer system  201  may also be implemented using specially-programmed, special-purpose hardware. In computer system  201 , the processor  202  is typically a commercially-available processor, such as those available from the Intel Corporation, Sun Microsystems, or Motorola. The processor  202  usually executes an operating system which may be, for example, those available from the Microsoft Corporation, Apple Computer, Sun Microsystems, Palm, Inc. or other UNIX-based operating systems available from various sources.  
         [0036]    It should be understood that the invention is not limited to a particular platform, processor, operating system, or network. Also, it should be apparent to those reading this application that the present invention is not limited to a specific programming language or computer system and that other appropriate programming languages and other appropriate computer systems could also be used.  
         [0037]    In this application we generally consider that a database search operation, or query, is facilitated by breaking down the query into a plurality of query elements  400 . The query elements  400  are predefined and comprise a set of allowed query elements  302 . A user  100  uses a selector  510  built into a user interface  303  to select individual values from a domain comprising the allowed query elements  302 . A particular chosen query element value, which is chosen from the domain or list of allowed query element values  302 , is referred to as a selected query element value  430 . Thus, the user  100  chooses a selected query element value  430  from the list of allowed query element values  420  which are defined for each query element  400 .  
         [0038]    [0038]FIG. 3 shows an example graphical user interface  50  according to one embodiment of the invention. An interface is provided that displays query elements  400  and a list of allowed query element values associated therewith. The list may be displayed, for example, using a selector  510 , such as a data selection box, having a drop down list containing all of the allowed query document values  420 . The selector  510  may also accept free text, and display matching values associated with the free text entry. Drop down boxes, menus, and text entry field are examples of methods for accepting selection information from users. It should be understood that other methods for conveying or displaying the query elements  400  and their allowed values  420  may be used. By limiting the user  100  to predetermined allowed query element values  420 , the system guides the user  100  in properly forming queries, and obtaining more relevant results. The user interface  50  may be implemented, for example, using HTML, XML or other ways for representing user interfaces.  
         [0039]    [0039]FIG. 4 shows two query elements  400  in more detail. An exemplary “Do” and “What” query elements  400  illustrate how a query element  400  can have several allowed query element values  420  from which a user  100  can select a selected query element value  430 . Here, the “Do” query element  400  is associated with a selector  510  that drops down a list of allowed query element values  420 , or a domain. The allowed query element values  420  include the entries “Apply for; Renew; Inquire about, Cancel; File for; Report lost.” From this list of allowed query element values  420 , the selected query element value  430  “Renew” is chosen. Similarly, the “What” query element  400  is associated with a selector  510  that allows a user  100  to choose from preassigned allowed query element values  420 . In this example the “What” query element  400  is associated with allowed query element values  420  “401K; Tax return; Social security; Driver&#39;s license; Passport.” The query element value “Driver&#39;s license” has been selected as the selected query element value  430  for the “What” query element  400 .  
         [0040]    Other query elements  400 , such as those depicted in FIG. 4, can be similarly assigned a selected query element value  430  for each. Note that it is possible for a user  100  to make no selection for one or more query elements  400  in some embodiments.  
         [0041]    Additionally, each individual query element value may be assigned a query element relevancy  425 . The query element relevancy  425  is a measure of the relevance of any individual query element value to others in the same domain or list of allowed query element values  420 . Assigning such relevancy  425  can be helpful in guiding a user  100  through the query process, and in presenting and ranking other relevant query results for the user  100 .  
         [0042]    [0042]FIG. 5 shows a block diagram of a database query system  30 , sometimes referred to as a “vortal” search service, that performs a database query according to one embodiment of the invention. Server  301 , upon which various aspects of the invention may be implemented, may be for example, a general purpose computer system, as described above with reference to FIG. 2. Server  301  collects information provided by one or more clients  209 . The clients  209  may be coupled to, or in use by a user  100 . Clients  209  may also be general purpose computers.  
         [0043]    According to one aspect of the invention, server  301  provides a user interface  303  through which database queries are performed. This user interface  303  may be, for example, a hypertext markup language (HTML) interface presented on a query result presenter, such as a Web browser. A structured query constructor  304  may be provided to facilitate the formulation of queries into query elements  400 . Other types of interfaces are available. The user interface  303  allows the user  100  to select from a plurality of allowed query element values  420  for various query elements  400 . By selecting a particular element/value combination, a query is defined. The query elements  400  and values are provided to a query element-indexed searcher  112 , which accesses the database  150  by using query elements  400  and their selected query element values  430  as an index. The database  150  may be indexed, for example, manually by an editor, human or machine, or by a database administrator. The query results  118  of the query are then presented as ranked displayed results  322  to the user  100 , and may be presented according to relevance by a query result presenter  120 . The query results  118 , for example, may be one or more information objects from the database  150  such as links.  
         [0044]    In one embodiment of the invention, a relevancy is determined for each database object for domains having multiple possible values. In this manner, the query is executed based on values specified for each element against the classification of the information in the database rather than the information itself. Because keywords do not have to be indexed or NL analysis performed, search time is reduced. Also, because more relevant information is indexed, the result displayed to the user is more relevant, and unnecessary effort reviewing irrelevant links is not required.  
         [0045]    It should be understood that one or more components of database query system  30  may be implemented on one or more systems, and the invention is not limited to a single system. For instance, the database  150  may be implemented on a separate general purpose computer system that communicates with the database query system  30  through a communications network  200 . Other configurations of the system are possible.  
         [0046]    [0046]FIG. 6 shows a logical data model  40  that may be implemented in the system  30  shown in FIG. 5. A query element  400  is provided which is used to describe an aspect of the query to be performed on a database  150 . For example, a query to be asked of the database may comprise one or more of the following query elements  400 :  
         [0047]    Who (element 1): the subject of the question  
         [0048]    Do (element 2): the action performed  
         [0049]    What (element 3): the object of the action  
         [0050]    Where (elements 4): the location for the action  
         [0051]    When (element 5): when the action was or will be performed  
         [0052]    In the context of a special purpose Internet site such as a government-related Internet site that handles processing of drivers&#39; licenses, auto registrations, passports, tax returns, postal services, social security, and other aspects of government, the following query elements  400  and allowed values may be preassigned:  
                                           Who (element 1):   Values:   [I, my spouse, my family, my parents,               etc.]       Do (element 2):   Values:   [Apply for, renew, inquire about, cancel,               file for, travel, know, etc.]       What (element 3)   Values:   [Driver&#39;s license, 401K, passport, tax               return, USPS, SSA, etc.]       Where/From_To   Values:   [In the U.S., State, County, City, Zip,       (elements 4 and 5)       Country, etc.]       When (element 6):   Values:   [in yearly increment, not applicable, etc.]                  
 
         [0053]    For example, a user  100  may construct a query using the allowed query elements  420  and corresponding selected query element values  430  such as “[I] [apply for] [passport] [in U.S.]” or “[I] [renew] [driver&#39;s license] [in Massachusetts].” Sometimes the database  150  is indexed by the query elements  400  and the corresponding selected query elements  430  values, thus keyword or NL interpretation is not required.  
         [0054]    Data may be classified in the database  150  by assigning or associating more than one value for each query element  400 . For example, a Massachusetts driver&#39;s license application form (or reference or link thereto) may be stored as an information object in the database  150 , and may be indexed by the following query elements  400  and their selected query element values  430 :  
                                                       Who:   [All]           To:   [apply for]           What:   [driver&#39;s license]           Where:   [MA]           When:   [not applicable]                      
 
         [0055]    Therefore, a user  100  requesting any information with [apply for] [driver&#39;s license] and [MA] as “To”, “What”, and “Where” elements will retrieve database information objects indexed by these query elements  400 . In the database  150 , an example entry for a database information object, such as a Uniform Resource Locator (URL) or a link associated with applying for a driver&#39;s license in Massachusetts may have the following entry:  
         [0056]    &lt;link information&gt;&lt;All&gt;&lt;apply for&gt;&lt;driver&#39;s license&gt;&lt;MA&gt;&lt;not applicable&gt;As discussed, a relevancy  425  may be assigned among all the possible allowed query element values  420  for a query element  400  which will allow the system to determine the most relevant response to a query. For example, the “To” element may have two allowed query element vales  430 —“Apply for” and “Renew.” A 60% relevancy may be assigned to both values, such that if a user  100  selects “Apply for” as the selected value of the “To” query element  400 , the information object assigned a value of “Renew” for the “To” element will also be retrieved, along with the “Apply for” information object. Because the user  100  specified “Apply for,” the database entries associated with the query element “Apply for” are assigned a relevancy value of 100% (a direct hit). Those database entries having a related query element will be displayed according to their assigned relevancy  425 . Thus, a relevancy  425  may be assigned based on relevancy between query elements  400 . This relevancy  425  may be assigned, for example, when database  150  entries are classified.  
         [0057]    According to another aspect of the invention, the query results  118  returned to the user  100  are arbitrary numbers that are used by the system to refer to the actual links. In this manner, other Internet services are prevented from stealing query content, such as search results, from the database server  301 . According to one embodiment of the invention, each link is assigned an arbitrary number, and the arbitrary number is associated with the actual link through a mapping that may be stored, for example, on the database server in a mapping table  601 . The clients  209  query the server  301  and obtain query results  118 , which include links that contain the address of a server and the arbitrary numbers instead of the actual links. When a user  100  selects a link, the resulting link request is brokered by the server  301  to the corresponding destination. That is, the server  301  performs the request on behalf of the client  209 , and the content is returned by the server  301  to the client  209 . The server  301  may also filter and replace that content, such that the client  209  does not obtain actual links; that is, the server  301  provides substituted links. Another way to think of this is to consider that information objects retrieved from the database  150  are mapped into mapped information objects.  
         [0058]    Further, the mapping table  601  may also include other state information relating to the link, such as last check time  604  and last check status  605 . In this way, state information for the links may be maintained by the server  301 , and the server  301  may determine if these links are still valid.  
         [0059]    [0059]FIG. 7 shows an example of a mapping table  601  for mapping link information, the table  601  being maintained by, for example, the search system  30  shown in FIG. 5. The table  601  includes link information  602  which may be URL information indicating the location of a resource. Associated with each URL is an arbitrary identification (ID) number  603  which is provided to a user  100  in response to queries. ID number  603  may be, for example, a unique identifier used to uniquely identify a URL. ID number  603  may also be assigned sequentially by the database system  30 . For example, ID number  603  may be appended to the address of the server  301 , and when a user  100  selects a link of the response, the user  100  is directed to the arbitrary link assigned by the server  301 . The server  301 , in response to the request for the arbitrary link, accesses the mapping in the table  601 , and obtains the content requested. The server  301  may also filter content by replacing links with arbitrary ID numbers  603  as the information is returned to the client  209  or the user  100 .  
         [0060]    Table  601  includes link state information such as last checked information  604  which indicates when the link was last checked. State information may also include a last check status  605  which indicates the status of the link at the time at which the link was last checked. It should be understood that other methods for maintaining link information may be used.  
         [0061]    Having now described a few embodiments of the invention, it should be apparent to those skilled in the art that the foregoing is merely illustrative and not limiting, having been presented by way of example only. Numerous modifications and other embodiments are within the scope of ordinary skill in the art and are contemplated as falling within the scope of the invention as defined by the appended claims and equivalents thereto.