Abstract:
An electronic catalog requisition system includes software for efficiently selecting items from a database. The software accepts search terms from a user, and then executes a sequence of search strategies on the database which may include a proximity search, a word count search, and a fuzzy logic search. The sequence is terminated when a search algorithm has uncovered at least one match. Each database entry has a corresponding product category. A list of categories from each of the matching products is dynamically compiled and displayed to the user. The user can page through the list of displayed matches, or alternatively can create a subset of the list by selecting only the items within one of the categories. In addition, the user can further refine the list of items by selecting those items having a particular attribute. The software can also maintain a list of synonyms for attributes as an aid for finding appropriate matches within the database. Natural adjectives to certain of the attributes are recognized as further refinements to the search criteria. The invention has the advantage that users with a wide range of skills and/or familiarity with products can quickly find the products that they need. The software has the additional feature of creating electronic requisitions for the products listed in the database.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of prior application Ser. No. 09/514,524, filed on Feb. 28, 2000, now U.S. Pat. No. 6,321,224 which is a continuation of prior application Ser. No. 09/058,553, filed on Apr. 10, 1998 and issued Feb. 29, 2000 as U.S. Pat. No. 6,032,145. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to software for database interrogation and manipulation and, more particularly, to a method and system for retrieving database records using predefined classifications, and further coupled with search refinement options based on parametrics and classification. 
     BACKGROUND OF THE INVENTION 
     Searchable electronic catalogs are commonly used in support of various electronic commerce and purchasing functions. These catalogs must have a user interface for selectively retrieving data records. Software engineers desire to make the user interfaces as simple as possible to operate, because complexity of the user interface can be a detriment to sales from the catalog. Simplicity becomes particularly important when the catalog is intended to be accessed by users with varying levels of skill or training. 
     User interfaces that are simple to operate should have the capability to handle almost any type of user input. In the case of an electronic catalog, if the user knows the exact part number of the desired product and enters the part number correctly into the user interface, then the database search engine will quickly identify the desired record from the database based on an exact match with the search string. In a more general case, the user may have only partial information about the desired product, or may incorrectly type the search string. 
     Danish et al. in U.S. Pat. No. 5,715,444 disclose a process for identifying a single item from a family of items in a database. A feature screen and search process present the user with a guided nonhierarchical parametric search to identify matching items based upon user specified criteria and priorities. Also disclosed are a method and system appropriate in an Internet environment. 
     Cochran et al. in U.S. Pat. Nos. 4,879,648 and 5,206,949 disclose a method of variably displaying search terms in which two control inputs are used to select a plurality of terms for a plurality of categories. A term in a visible position on the screen becomes a search term or a qualifier for other records in the database. The search results are dynamically formed on the basis of selected search terms. The search results can also be grouped in fixed or static lists. 
     Blutinger et al. in U.S. Pat. No. 5,231,566 disclose a method and apparatus for producing a catalog. The catalog has the characteristic that all like items in the database have the same catalog item number, whereas different items have different catalog item numbers. 
     Geier et al. in U.S. Pat. No. 4,984,155 disclose a system for enabling a customer to operate a data terminal for placing an order for goods or services. The customer is permitted to enter an invalid catalog number that is used as a key to display a series of products having catalog numbers similar to the catalog number entered by the customer. 
     Prior catalog search algorithms typically employ one of two search strategies. The first strategy is a keyword search for selecting database records based on matching text strings. The second strategy is a hierarchical search for selecting database records based on lists of classifications from which to narrow and select the database records. Each of the two search strategies has disadvantages that can make it difficult for users to find their desired database records. 
     The keyword search strategy has the disadvantage that users must be familiar with the appropriate key word terms that are likely to yield the desired data records. In addition, it is not always possible to quickly collect groups of logically related data records. If a close match is found, but it is not the desired exact match, it is not always possible to utilize the information in the close match to quickly identify all similar data records. A keyword search engine does not typically have a “more-like-this” function that operates on close matches to identify similar items within the database. 
     The hierarchical search strategy can take advantage of a logical grouping of data records. This search strategy is best suited for finding data that break down logically into successively greater levels of detail. This search strategy is most effective when the data have been carefully edited and structured within a database. Finding a single relevant record can quickly lead to all other relevant records, as long as the grouping logic relates to the way in which the data are used. 
     Thus, a “more-like-this” function can quickly identify all similarly classified records in the database. 
     The disadvantage of the hierarchical search strategy is that users may not always anticipate the proper classification of certain records, and may search the wrong categories for their desired database record. The user is tied to the logical structure of the data, and must learn to navigate the predefined structure of the database in order to locate particular data records. 
     It would be desirable to allow free-form text searching, with no prerequisites for format or content. Thus, it would be desirable to have a system capable of identifying the database records most likely to be the desired choice of the user, even when the user inputs a search string having misspelled terms, word fragments, or other characteristics of the item being sought. It would further be desirable to take advantage of natural relationships and logical groupings within the data records to compile lists of similarly classified data records. The prior art has not disclosed a system that provides a simple and convenient user interface coupled with a search engine that has the architecture and advantages of the present invention. 
     SUMMARY OF THE INVENTION 
     The present invention provides a simple user interface that combines the ease of keyword searching with the advantages of search refinement through classification or parametric selections. The text searching is improved through the use of sequential search algorithms that are designed to maximize the chances of identifying the desired data records. The search refinement is presented as a simple selection from a list of classifications that is dynamically compiled based on the results of the keyword search. The output to the user reports on both generic and category-specific product characteristics. 
     According to the present invention, a method of selecting data records in a catalog database comprises the following steps: inputting search terms to a user interface; testing the search terms against the catalog using a sequence of search algorithms, wherein each search algorithm is applied against the database to identify matching catalog records comprising a set; terminating the sequence of search algorithms when at least one record becomes a member of the set; compiling a unique list of classifications from each member of the set, said list comprising at least a first classification; displaying at least a portion of the set along with the list of classifications; creating a subset of the set by selecting members having the first classification; and displaying the subset. 
     The invention comprises a database along with a search engine. The database typically consists of category descriptions, manufacturer&#39;s name, manufacturer part number, short text description, and parametrically composed descriptions. Product categories and characteristics are represented directly by tables and columns respectively. 
     The search engine executes a series of text string matching algorithms, in sequence, until at least one match is identified from the catalog. The sequence comprises proximity searching, string matching, stemming, fuzz logic, and soundex matching. For example, if an exact match is found, the search halts when all exact matches have been identified, and there is no further recourse to other search algorithms. If no exact match is found, then the search terms are manipulated to identify strings with similar roots. If, again, no match is found, the search terms are tested further according to other algorithms, such as fuzzy logic and soundex, until a match is found or the search engine reaches its logical termination. 
     One of the important aspects of the search strategy is that the searchable terms include the predefined classification terms as well other attributes and parameters of each catalog entry. This means that the freeform text input will show text string matches against any classification name or parametric name. This feature enhances the possibility of finding the desired data record based on the keyword search engine. 
     Each catalog entry has an associated classification according to type, and a list of unified classifications is compiled dynamically from the identified matches. Dynamic compilation refers to the process of continuously updating the list of classifications whenever new matches are identified. This insures that the list continuously and accurately reflects the range of classifications of the identified matches. The list is unified in the sense that each classification is listed only once, even when the identified matches have multiple records with the same classification. The classification list is presented to the user along with the list of matches as an aid to the user for further refining the search methodology. 
     Those skilled in the art will recognize the benefits and objects of this invention, which include but are not limited to the following: providing a database search engine that can quickly and easily lead users to a desired database record; combining the benefits of key word searching with the benefits of hierarchical searching; providing an interface that will process any type of user entry, including misspelled words and word fragments; displaying a list of product categories that can be used to narrow the database search criteria; providing a search engine and database structure that maximizes the likelihood of finding the desired database records based on a simple user interface. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The subject matter which is regarded as the invention, together with further objects and advantages thereof, may best be understood by reference to the description herein, taken in conjunction with the accompanying drawings, in which: 
     FIG. 1 is a block diagram representation of an electronic catalog requisition system employing the present invention. 
     FIG. 2 a  is a logic diagram of a search engine according to the present invention. 
     FIG. 2 b  is a display and refinement of search query results. 
     FIG. 3 is a representative display of the results of a search at the user interface. 
     FIG. 4 is a representative display of the results shown in FIG. 3, and further narrowed by, selection of a single classification from the user interface. 
     FIG. 5 is another block diagram representation of an electronic catalog requisition system employing the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 is a functional block diagram representation of an electronic catalog and automated purchase requisition system. An application server  12  is connected to interact with a database  14  which resides in a computer memory storage device  16 . Users of the system have workstations  18  that are connected to the application server  12  through a wide area network such as the Internet. Commands entered into web browser software cause information to be extracted from the database  14  and displayed at the workstation  18 . 
     The database  14  is an electronic catalog of products. The database  14  is preferably constructed in a manner known as a “universal” catalog, in which like products from different suppliers have a single database record. Constructing a universal catalog typically requires an editor to ensure that each unique product has a unique database record. This database architecture has the advantage that users will be able to recognize identical products from different suppliers. In contrast to a universal catalog, an aggregated catalog is merely an aggregate of product information from multiple suppliers. The same item may be listed several times in an aggregated catalog, though not usually in a consistent manner, with the undesirable result that users may not recognize that different database records actually refer to the same product. 
     In one embodiment of the invention, the software  10  is configured to access one of several electronic catalogs. The selection of a catalog is based on the likelihood that the catalog will have the desired item. As such, there must be a standard query format for each of the catalogs so that the same search string can be used to determine possible matches against each catalog. The match results can then be used by the software  10  to select among the catalogs. The type or format of the catalog is irrelevant as long as the catalog will respond appropriately to a text query from the software  10 . For example, the catalog may reside within a relational database or may reside within an object-oriented database. 
     Referring back to FIG. 1, the storage device  16  may be a disk drive, a tape drive RAM, or any of the known computer data storage devices. The application server  12  may reside in a computer attached directly to the storage device  16 , or alternatively may be connected to the storage device  16  through a network. In each case, the application server  12  queries the database  14  and directs the results to the workstation  18 . 
     Software  10  is executed within the application server  12 . The software  10  follows an algorithm as shown in the logic block diagram of FIG.  2 . The user inputs a search string, as shown in block  100 . The search string is free-form, meaning that the string may be any combination of alphanumeric characters or search terms. No particular syntax is required for the search string. The search string may comprise search terms in any order. For example, the search string could include the name of an item, a part number for an item, or any descriptive attribute of the item. 
     The software  10  is designed to handle misspellings, word fragments, or any other string that may lead a user to find the desired product within the database  14 . 
     The software  10  preferably has a single text box for search strings, shown as box  300  of FIG.  3 . The example search string in box  300  is “bic pen red” which represents a combination of manufacturer name, classification, and attribute. It has been found that users desire the simplicity of typing strings at a single location, without differentiating whether the string represents a product name, a product manufacturer, or a product attribute. Alternatively, there may be separate text boxes for different types of search strings. 
     The software  10  performs a proximity query which will try to find an exact match of the search string within the database  14 . Each record within the database is tested against the search string to find records that contain all of the search terms in proximity to each other. The highest quality match will be a record in which all terms appear in the same order as the search string. A lower quality match will have the terms in a different order, or may have the terms separated by other strings. The proximity query is a well-known procedure in the art of computer science, and certain commercial databases offer a proximity query function. An example of a database software package having the aforementioned function is Oracle  8  and the associated context cartridge, supplied by Oracle Corporation of El Segundo, Calif. 
     At the conclusion of the proximity query, the software  10  checks to see if any matches were found, as shown in block  102 . An exact match will lead the software to test whether price and vendor information need to be provided to the user, as shown in block  112 . If no exact match is found, the software  10  sequences to the next type of search strategy. 
     Block  104  in FIG. 2 a  shows the preferred second sequential search algorithm. Since no exact match has been found, the software performs a word count query in which individual words or search terms within the search string are checked against the products in the database  14 . The strategy at this point to find products within the database  14  that may match some of the descriptive terms in the search string. The word count query may also apply a stemming function to search terms to identify similar root words. 
     Block  106  test the results of the word count query to determine if any matches have been identified. If at least one item from the database  14  has been returned by the search algorithm, the software  10  proceeds to block  112 . Otherwise, the software  10  executes the next algorithm in the sequence of search algorithms. 
     As shown in block  108 , the next search algorithm in the sequence is preferably a fuzzy logic query. In this context, a fuzz logic algorithm may also be known in the art as a “word wheel” or other name associated with an algorithm for testing combinations and permutations of the alphanumeric characters in the search string. The intent in block  108  is to identify products in the database  14  having any descriptive similarity to the search string. For example, a user who enters a search string having a typographical error will not generally find an exact match within the database  14 , but a fuzzy logic algorithm may select the desired product on the basis of similarity with the search string. 
     The software  10  may also rank the degree of similarity between each matched database record with the search string. For example, records with a larger number of alphanumeric character matches against the search term will be ranked higher than records with only a few matching characters. Ranking algorithms are found in several commercially available software packages including Oracle  8 . 
     There are other possible sequences of search algorithms, but in general it is desirable to execute the narrowest, or most specific, search first. The sequence should proceed with search algorithms according to the scope of each algorithm. For example, a search for the specific search string is the narrowest in scope, whereas a search for related search strings will be broader in scope because it will likely return a wider range of matches. 
     An additional type of search algorithm not specifically shown in FIG. 2 a  is a “soundex” or “sounds-like” search, in which the search string is tested against database records for similarity in sound. 
     If any match is found as a result of a search algorithm, the successive search algorithms will be skipped and the software  10  will proceed to display the results. If the software  10  has been configured to add price and vendor information, that will also be added to the display as shown in block  116 . In the unlikely event that no matches were found after completion of the entire sequence of search algorithms, the software  10  will proceed to the display block  114  with a message indicating that no products were found. 
     The display will have several areas of information, as shown in FIG.  3 . The search string is shown in a text box  300 , preferably located in the upper-left comer of the display. The list of matching items is shown in a display list  302 . The display list  3702  includes the category, the manufacturer name, the manufacturer part number, and descriptive attributes. 
     A compilation of each unique category of product, compiled from the list of the matching items, is shown in a category display area  304 . If several different categories of products were found during the search, then each category will be displayed along with a corresponding radio button  306 . 
     Returning to the logic of the software  10 , FIG. 3 is representative of the logic contained in block  118  of FIG. 2 b . If the desired item from the catalog is not immediately visible in the display, the user has the option of paging through the remaining items in the list by clicking on button  308  in FIG. 3, which is shown as logic block  120  in FIG. 2 b . If the desired item is found, no further searching is required, and the logic of the algorithm drops to block  134 . 
     As an alternative to paging though a lengthy list of products, the user can narrow the list by selecting one of the categories. For example, FIG. 3 shows that two different categories of items were found: pens and pea refills. Since there are  29  matching items (only the first  10  are shown), the selection of radio button  306  will narrow the list to include only pens and not pen refills. A new display will be generated, shown in FIG. 4, wherein the updated display list  402  has 27 items which do not include pen refills. In this embodiment, selecting a category will be restrictive in terms of the items in the display list  302 . This procedure is shown as logic block  124  in FIG. 2 b.    
     In an alternative embodiment of the invention, selecting a category will generate a new display list  302  containing every item in the catalog associated with the selected category. In this alternative embodiment, selecting a display list may be expansive in terms of the number of items shown on the display list  302 . 
     A further alternative is to select only items having a particular manufacturer. For example, FIG. 3 has a button  310  which invokes a screen containing a list of all manufacturers of the products shown in the display list  302 . Selecting one of the manufacturers will cause the software  10  to narrow the display list  302  to include only items from the selected manufacturer. 
     In general, items within the catalog will have parameters that can be selected to restrict the display list  302 . For example, a parameter for pens may be “ink color” and has values of blue, black, or red. In the event that pens are selected as a category, the display list  302  may be further restricted to pens of a single color. This process is referred to herein as parametric refinement. 
     In the preferred embodiment of the invention, the algorithm will have a list of synonyms for each attribute. The search algorithms can replace individual search terms with appropriate synonyms for purposes of matching data records. The attributes are normally used as part of an algorithm for finding matches, and the use of synonyms for the attributes gives additional flexibility to the range of search strings that will produce meaningful matches. 
     Another way to increase the flexibility of the search algorithms is to allow natural adjectives in the search string to help select certain attributes. For example, if there is a category for computers, and the category has an attribute for processor speed, then the adjective “fastest” in the search string could be used to select the fastest computer. Slower computers would be eliminated from the display list  302 . 
     Yet another way to increase the flexibility of the search algorithms is to assign categories alternative roles such as, but not limited to, problem spaces and applications. In this embodiment, the items found by the query are actually predefined queries that generate lists of actual data records from the database. Thus, selecting a category becomes equivalent to submitting a predefined query to the database. 
     If the search did not reveal the desired products from the database  14  within the list, the user is prompted to try a new search string, as shown in block  128  of FIG. 2 b . Alternatively, the user may select an item, and a predefined query within the database record for that item will be input to the software  10  as a new search string, resulting in a new and updated list of categories being displayed to the user. 
     FIG. 5 is an alternative simplified diagram that explains the logic of the software  10 . Block  501  is representative of web-browser software that executes on a user&#39;s local computer. The text box, such as shown as  300  in FIG. 3, is presented to the user. The user enters the text description, as shown logically by block  502 . The sequence of search algorithms is performed on the text description, as shown logically by block  503 . The user picks an item for a display list, such as the list shown as  302  in FIG.  3 . The user further refines the search with one of several options as shown in logical block  504  in FIG.  5 . The user may enter more text, less text, or better (more descriptive) text and thereby generate a new display list  302 . Alternatively, the user may select a category, and further may select a parametric value (also called an attribute). Once a desired item is identified, the user is presented with supplier and pricing information, as shown in logical block  505 . 
     The electronic requisition system can provide links to further information about items within the database. The further information can be stored within the database  14 , or alternatively may be stored at a remote computer accessible through the Internet. For example, buttons on the display screen can invoke links to web sites that contain relevant information. 
     Items within the catalog are preferably cross-referenced so that related items can be quickly located. For example, if the user selects a printer from the catalog, the appropriate toner cartridge can be immediately located by pressing a button on the display list. 
     Once a user identifies the desired product from the database  14 , the software  10  can generate a purchase requisition having preformatted price, vendor, and user information. Individual contract terms and pricing information can be accessed by the software  10  to be reflected in the requisition. The requisition can be sent electronically to the vendor for processing. 
     It will be apparent to those of skill in the appertaining arts that various modifications can be made within the scope of the above invention. Accordingly, this invention is not to be considered limited to the specific examples chosen for purposes of disclosure, but rather to cover all changes and modifications which do not constitute departures from the permissible scope of the present invention. Having thus described our invention, what is desired to be secured and covered by Letters Patent is presented in the appended claims.