Abstract:
A method for creating a web-based database application that is data dictionary driven is disclosed. A web site, containing various computer programs, data for a database application and a data dictionary describing both the structure of an application database and the requirements for the database application, creates web pages for facilitating the execution of a database application over the internet. The method comprises the steps of creating, updating and maintaining an on-line data dictionary, and creating and initially populating a database for the application. The various programs at the web site create web pages for the application, update the data dictionary and facilitate modification of the data structure for the application. The data dictionary may be initialized: from electronic data uploaded to the web site; from the data-dictionary records describing an existing web-based application; or directly by the user via a web interface. The resulting application allows the user to enter information, view information, select the records to be viewed, and make changes to the application such as form captions, fields displayed, colors used, database structure, and other contents of the data dictionary.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates generally to data bases and more particularly, to a method of using a data dictionary to create a web-based database application.  
       BACKGROUND  
       [0002]     A data dictionary is an electronic repository of information that describes many of the components of a database application. A data dictionary for web-based database applications may contain information describing one or more of the following: (1) the web application&#39;s database structure (tables, fields, indices, and relationships), (2) database characteristics (required fields, field masks, etc), and (3) the web application&#39;s components (menus, forms, reports, export formats, etc.). It may also contain information relating to (4) the text or images that are displayed on web forms and menus (for buttons, captions, labels, form titles, messages, etc.), (5) the fonts and colors used to display text on the web forms, (6) the location where the various items are to be displayed on the form, and (7) programming code that is to be executed when the web application is run.  
         [0003]     A web-based database application program consists of two primary components: (1) the “applications” component, which is responsible for running the database application, allowing users to enter information, view information, and select the records to be viewed, and (2) the “data dictionary maintenance” component, which allows the system administrator to make changes to the application (application specifications, form captions, fields displayed, colors used, database structure, and other contents of the data dictionary).  
         [0004]     Using a data dictionary as the underlying concept for a web-based database application provides many advantages. Some of these advantages include: (1) development of web-based database applications without needing a programmer or web developer; (2) minimal cost to set up a sophisticated, user-friendly web database application that typically includes forms for filtering, listing, and reviewing records in a database, menus, etc.; (3) the ability of a user to change the look and feel of the application pages without needing a programmer or web developer; and (4) various levels of security to limit who can review or change the data.  
         [0005]     Web pages fall into two general categories—static and dynamic. Static web pages are presented to the user (after being interpreted by the user&#39;s browser) without modification. These files generally contain only HTML codes, text, and graphics, and have the file extension of HTM or HTML. Examples include help text and menus. Dynamic web pages, on the other hand, have program code (or pseudo-code) imbedded in them which dynamically creates the HTML code that is sent to the browser. The program code can be used to retrieve data from a database, create HTML code for displaying the data in a table, etc.  
         [0006]     Many internet sites currently host web-based database applications. At virtually all of these sites, the application is either provided by the user or the service provider. In both of these cases, a significant amount of programming is usually required for each web page that contains data which is extracted from a database in real-time. In order to reduce development time, many programmers use web-development tools which contain “wizards”. Wizards are programs that create web pages based on information about the application that is provided by the developer when the “wizard” is run. There are two problems with this approach: (1) once the “wizard” is run, the user often has to make extensive changes to the code produced and (2) the information provided to the “wizard” is usually not saved; the developer must re-enter the data when re-running the “wizard”.  
       SUMMARY OF THE INVENTION  
       [0007]     The present invention allows for web-based database applications to be run based on data in a data dictionary. A central web site contains both the application&#39;s data and the data dictionary. The present invention includes the following steps and functions:  
         [0008]     A central web site is set up with a data dictionary, a data base server, programs which produce menus and forms for a data base application, programs which produce menus and forms for the data dictionary maintenance procedures and a project directory.  
         [0009]     The data dictionary contains information for both the data dictionary maintenance forms and sample application forms. The data base server may have new databases added to it. Programs which produce menus and forms for a database application and perform the functions needed to run the database application such as add, change, and delete records, perform data validation, etc. Programs which produce menus and forms for the data dictionary maintenance procedures perform the functions needed to update the data dictionary and change the application&#39;s database structure. A project directory is created dynamically for each database application when a new database project is started.  
         [0010]     A user opens a web page at a central web site and is led though a series of steps to create the database application. The invention allows for a database application to be created in one of three ways. The user may upload electronic data to a web site. A program on the web site creates a new database for the user and copies the data dictionary tables into the database. A second program on the web site reads the electronic data and updates the data dictionary with information about the database structure and requirements (e.g., table names and properties, field names and properties, index names and properties, relationships among the tables, etc). A third program on the web site then creates the application tables in the database. A fourth program reads the data uploaded by the user and populates the application tables in the database.  
         [0011]     Alternatively, the web site may contain many sample database applications. The user selects one of the sample applications, and a program on the web site creates a new database application for the user.  
         [0012]     In another alternative, the user may request that the system create empty database for the application. The user then uses the “application maintenance” programs (see below) to create the application tables and fields.  
         [0013]     In should be noted that for each of the three approaches described above, a program on the web site creates a directory on the web site for a user&#39;s project and copies several files into the directory.  
         [0014]     The user may start the database application by using a web browser to request a web page in the user&#39;s project directory. The application allows the user to enter or change information, view information, select the records to be viewed, and exported, reported, or exported.  
         [0015]     The present invention provides three methods used by a dynamic web page to create content used in the database application: (1) A program at the web site creates application-specific dynamic web pages based on the data about the application in the data dictionary (these pages are created in the user&#39;s project directory whenever the structure of the database or application requirements change). These web pages do not need to refer to the data dictionary when the application is run. (2) The database application uses dynamic web pages which derive all of the information necessary to display the application&#39;s web pages from the data dictionary associated with the application. For this method, a standard set of dynamic web pages in the user&#39;s project directory read the data dictionary and dynamically create the application&#39;s content. (3) A final method uses a combination of the previous two—dynamic web pages are created specifically for the application, but these web pages still need to get information from the data dictionary when creating the web page displayed to the user.  
         [0016]     An option in the database application allows the user to start the “application maintenance” module. The programs in this module allow the user to upload additional data, update the data dictionary and change the database structure. This includes, but is not limited to, changing the text or images that are to be displayed on the web forms and menus (for buttons, captions, labels, form titles, messages, etc.); changing the fonts and colors to be used to display text on the web forms; where the various items are to be displayed on the form; and specifying programming code that is to be executed when the web application is run. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0017]     Features of the present invention will be more apparent from the following description of the preferred embodiments with reference to the accompanying drawings, wherein:  
         [0018]      FIG. 1  illustrates the main components of a data dictionary-driven web-based database application;  
         [0019]      FIG. 2  illustrates the components of the system that are contained at the Web site;  
         [0020]      FIG. 3  illustrates the components used to initialize the data dictionary based on electronic data provided by the user;  
         [0021]      FIGS. 3A-3G  illustrate screen shots of the sequence used to sign up for the service and to upload an electronic copy the data;  
         [0022]      FIG. 4  illustrates the components used to create the user&#39;s database based on the data dictionary;  
         [0023]      FIG. 5  illustrates the components used to upload the user&#39;s data and load the data into the Web site&#39;s database;  
         [0024]      FIG. 6  illustrates the components used to create the web pages for the application;  
         [0025]      FIG. 7  illustrates the components used to run the database application from the application-specific Web pages;  
         [0026]      FIG. 8  illustrates the components used to run the database application from the data dictionary;  
         [0027]     FIGS.  8 A-D illustrate screen shots of a data dictionary-driven database application;  
         [0028]      FIG. 9  illustrates the components used to maintain the data dictionary and user&#39;s database;  
         [0029]     FIGS.  9 A- 9 AK illustrate the screen shots of the various ways the data dictionary and user&#39;s database can be maintained;  
         [0030]      FIG. 10  illustrates the components used to create a copy of the application data;  
         [0031]      FIG. 11  illustrates the various tables in the data dictionary and how they are related; 
     
    
     DETAILED DESCRIPTION  
       [0032]     In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular techniques, etc. in order to provide a thorough understanding of the present invention. However, it will be apparent to one skilled in the art that the present invention may be practices in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known methods are omitted so as not to obscure the description of the present invention. Web pages described in the present invention are, for the most part, dynamic.  
         [0033]     A data dictionary-driven web-based database application is illustrated in  FIG. 1  and includes a central web site, a plurality of computers and the internet. The central web site includes a data dictionary, application data, and dynamic web pages. Each of the plurality of computers is connected to the internet and runs web browsers to display the application&#39;s web pages. The internet connects the plurality of computers to the central web site.  
         [0034]     The central web site, illustrated in  FIG. 2 , includes a central directory, a web site data base, an application project directory and an application database. The central directory includes common programs used in creating the database application pages (generic application programs) and maintaining the database requirements and structure (data dictionary maintenance Web programs). The web site data base contains sample applications and data dictionary tables that are used in displaying the web pages which are used to maintain the database requirements and structure. The application project directory (one directory for each project) contains application-specific web pages, generic application web pages, images for displaying on application pages, additional HTML code to be displayed on application web pages, and upload/download directory. The application database contains application data and data dictionary tables associated with the application.  
         [0035]     The initialization of a data dictionary is illustrated in  FIG. 3 . Application information is uploaded to the central web site and information is loaded into a data dictionary based on the uploaded application information. The uploaded information is electronic information about the database. A user uploads ( 1 ) (or emails) files of electronic data to the central web site. An application program on the central web site reads the files ( 2 ) and enters information about the application into a data dictionary ( 3 ).  
         [0036]     The electronic information can be in many forms, including PC-based databases (e.g., Microsoft&#39;s Access, FoxPro, dBase, Paradox, etc.), spreadsheets, and text files. The information for the data dictionary can be derived either from the database or spreadsheet (a Microsoft&#39;s Access MDB file contains information on table structures, required fields, etc.), or obtained explicitly from electronic data dictionary information. For example, a spread sheet could contain “sheets” for each table, and each “sheet” could contain information about the fields of the corresponding table, etc.  
         [0037]     The process of signing up for a service and uploading an electronic copy of data is illustrated in  FIGS. 3A  to  3 G. A central web site provides web pages which step or guide a user through the uploading process. A user signs up for service as a new customer ( FIG. 3A ) and enters information about his/her company ( FIG. 3B ). The user selects a method for creating the web-based application (uploading a file, creating an application from a template, or starting with an empty database) ( FIG. 3C ). The central web site creates an account for the user (insuring that the information was filled out properly) ( FIG. 3D ). The central site also creates a directory for the application, copies in the web pages needed to run the user&#39;s application, and creates an empty database ( FIG. 3E ). The user selects the file to be used to create the application ( FIG. 3F ), and, the file is uploaded to the central Web site ( FIG. 3G ). The system reads the uploaded file, determines the database structure, and updates the data dictionary with the information gleaned from the uploaded file. For example, from an Access MDB, the system can determine the name of each table, the name of each field in each table, the specifications of each field (e.g., required, default value, type, size, mask, etc.), the name of each index (and the corresponding fields), and the relationships among the various tables. From a text file (which has the field names in the first record), the system can determine the name of the table, the name of each field in each table, some of the specifications of each field (e.g., type, size, number of decimal places).  
         [0038]     A database for an application is created as illustrated in  FIG. 4 . An application program on the central web site reads the data dictionary ( 4 ) and creates the database for the application ( 5 ). The database could be stored either on a database server (e.g., Oracle, Microsoft&#39;s SQL Server, etc.) or on a file server (e.g., Microsoft&#39;s Access or FoxPro). It should be noted that if the files that the user uploaded are to be accessed directly by the web application, this step is not necessary.  
         [0039]     The uploading of a database for an application is illustrated in  FIG. 5 . A user uploads the files ( 6 ) of electronic data to the central web site (when the user signs up for service, the upload in this step is the same as the upload shown in  FIG. 3 , step  1 . This step allows for the user to upload electronic data after the application has been created). An application program on the central web site reads the files ( 7 ) and the data dictionary ( 8 ) and updates the application&#39;s database ( 9 ). The electronic data can be in PC-based databases, spreadsheets, text files, or other electronic formats.  
         [0040]     Creation of web pages for a web application is illustrated in  FIG. 6 . An application program on the central web site reads the data dictionary ( 10 ) and creates the web pages ( 11 ) that will be used to run the application on the central web site.  
         [0041]     The running of an application from the generated pages is illustrated in  FIG. 7 . The user is provided the URL for the web site. When the user enters the URL in a web browser ( 12 ), the main menu for the application is displayed. The user can then select application components to be run and view/change data in the database ( 13 ). The data dictionary was used to create the pages for the application but is not used by the application&#39;s pages. The sample pages displayed to the users are illustrated in  FIGS. 8A-8D .  
         [0042]     The running of the application from the data dictionary is illustrated in  FIG. 8 . The user is provided the URL for a web site. When the user enters the URL in a web browser ( 14 ), an application program on the central web site ( 15 A,  15 B) reads the data dictionary ( 16 ) and generates all of the web pages for the application (menus, selection criteria, data, and reports, etc.) as the user requests them, allowing the user to view/change data in the database ( 17 ). A web-based application consists of the following components illustrated in  FIGS. 8A  to  8 F.  
         [0043]     A menu for allowing the user to select the table to be viewed/changed ( FIG. 8A ). (The list of tables on the menu is based on the records in the “tWebTable” data dictionary where the “table type” field has the value “Primary”). A “list form” that lists a subset of records in the selected table ( FIG. 8B ). From the list form, the user can specify another subset of record to be displayed, sort the records by any of the column headings, change the number of records displayed on the list form, select a record to view in detail (where it&#39;s data can be changed), or display another form (filter, export, report, or new). A “filter form” that allows the user to select the records to be displayed or reviewed ( FIG. 8C ). A “record form” that allows the user do view the detail for each record, including data in child tables ( FIG. 8D ). An “export form” that allows the user to export data ( FIG. 8E ). A “report form” that allows the user to select a report to be run and to specify several aspects of how the report is to be displayed ( FIG. 8F ).  
         [0044]     The maintenance of a data dictionary according to exemplary embodiments of the present invention is illustrated in  FIG. 9 . The user starts the data dictionary maintenance application by selecting the “Admin” button on any “List Form” ( 18 ). The programs used in this service allow the user to modify all of the items outlined above: the web application&#39;s database structure, database characteristics, web application&#39;s components, the text or images that are to be displayed on the web forms and menus, the fonts and colors to be used to display text on the Web forms, where the various items are to be displayed on the form, and programming code that is to be executed when the web application is run. After the user updates the data dictionary ( 19 ), the application&#39;s web pages are re-generated ( 20 ) or the application&#39;s database structure is changed ( 21 ).  
         [0045]     FIGS.  9 A- 9 AK illustrate the various menu options and forms that are used to maintain the data dictionary and the structure of the application&#39;s database. (Note: where appropriate, each figure shows the figure which will be displayed when the indicated hyperlink or button is selected.) In order to provide security, the user is first prompted for the “Pin” that allows the user to “administer” the system ( FIG. 9A ). The main “Web Applications Maintenance” menu ( FIG. 9B ) enables the user to select the type of maintenance that is to be done. Clicking on a menu option (e.g., “Lookup Tables”) displays the next level of menus (e.g., “Lookup Tables”— FIG. 9C ). The “Lookup Tables” menu ( FIG. 9C ) displays links for each lookup table in the application (specified by the value “Lookup” in the “table type” field of the “tWebTable” data dictionary table). When the user selects a table, the system will display forms similar to those shown in  FIGS. 8B-8F . The “Application Specifications Maintenance” menu ( FIG. 9D ) is used to change those aspects of the application which are not related to the structure of the application&#39;s database. Clicking on a menu option (e.g., “Site Information”) displays form which allows the user to change the indicated specifications (e.g., “Site Information”— FIG. 9E ). The “Web Site Information Entry/Edit” form ( FIG. 9E ) allows the user to specify/change the name of the organization, the name of the application, etc. The “Applications Tables List” form ( FIG. 9F ) allows the user to specify the name that will be displayed for each table, the type of each table, the security level required to access each table, etc.  
         [0046]     When the user selects “Application Table Indices” from the “Application Specifications Maintenance” menu (see  FIG. 9D ), the “Table Indices Filter” form ( FIG. 9G ) is displayed, enabling the user to specify for which table the index information is to displayed. The “Table Indices List” form ( FIG. 9H ) displays information about each index for the selected table and allows the user to specify the name of the index and the order in which it will be displayed. When the user selects “Lookup Fields For Pick Lists” from the “Application Specifications Maintenance” menu (see  FIG. 9D ), the “Lookup Fields Filter” form ( FIG. 91 ) is displayed, enabling the user to specify for which table the lookup information is to displayed. The “Lookup Fields List” form ( FIG. 9J ) displays each field in the selected table and allows the user to specify the key field for the table and the fields that will be displayed in pick lists on the various forms. When the user selects “Fields Displayed On Forms” from the “Application Specifications Maintenance” menu (see  FIG. 9D ), the “Fields Displayed Filter” form ( FIG. 9K ) is displayed, enabling the user to specify for which table the field display information is to displayed. The “Fields Displayed List” form ( FIG. 9H ) displays each field in the selected table and allows the user to specify which fields are displayed on each form, the order in which the fields are to be displayed, the spacing for each field on the “Record” and “Filter” forms, etc. When the user selects “Fields Captions” from the “Application Specifications Maintenance” menu (see  FIG. 9D ), the “Fields Captions Filter” form ( FIG. 9M ) is displayed, enabling the user to specify for which table the field caption information is to displayed. The “Fields Captions List” form ( FIG. 9H ) displays each field in the selected table and allows the user to specify the captions to be displayed on each form.  
         [0047]     When the user selects “Fields Specificatoins” from the “Application Specification Maintenance” menu (see  FIG. 9D ), the “Fields Specifications Filter” form ( FIG. 90 ) is displayed, enabling the user to specify for which table the field specification information is to displayed. The “Fields Specifications List” form ( FIG. 9H ) displays each field in the selected table and allows the user to specify whether a field can be updated, if the field is required, the default value, the display size, etc. The “Web Application Maintenance-Buttons and Colors” menu ( FIG. 9Q ) allows the user to select which set of buttons or colors to change. ( FIG. 9Q  indicates the figures corresponding to each menu choice).  
         [0048]     The “Button Text-List Form Entry/Edit” form ( FIG. 9R ) allows the user to specify the text, tool tip, and picture associated with the buttons on the “List Form”. The “Button Text-Record Form Entry/Edit” form ( FIG. 9S ) allows the user to specify the text, tool tip, and picture associated with the buttons on the “Record Form”. The “Button Text-Filter Form Entry/Edit” form ( FIG. 9T ) allows the user to specify the text, tool tip, and picture associated with the buttons on the “Filter Form”. The “Button Text-Other Form Entry/Edit” form ( FIG. 9U ) allows the user to specify the text, tool tip, and picture associated with the buttons on the “New Form” and “Export Form”.  
         [0049]     The “Web Color Parameters List” form ( FIG. 9V ) allows the user to select a record which specifies the colors for one of the components the application. The “Web Color Parameters Entry/Edit” form ( FIG. 9W ) allows the user to specifies the colors for one of the components the application. The “Change Database Structure” menu ( FIG. 9X ) allows the user to change the structure of the application&#39;s database (add tables, add fields, etc)( FIG. 9X  indicates the figures corresponding to each menu choice).  
         [0050]     Selecting the “Add Tables From System-Wide Data Dictionary” menu option displays the “Add Table List” form ( FIG. 9Y ). The user then selects which tables to be added from the system-wide data dictionary. The user can also specify that the sample data is to be copied to the application&#39;s database. Selecting the “Add A Table” menu option displays the “Add Table Entry/Edit” form ( FIG. 9Z ). When the user clicks the “Insert” button the data about the table is saved in the data dictionary (the table cannot be created until the fields are specified in the next step). Selecting a “Change Table Structure . . . ” menu option displays the “Field Specifications Filter” form ( FIG. 9A A), which allow the user to select the table whose structure will be changed. When the user selects the “Apply Filter” button, the form in  FIG. 9A B will be displayed.  
         [0051]     The “Field Specifications List” form ( FIG. 9A A) allows the user to change the structure of a table in the database. For each new or existing field, the user can specify the field type, field size, index type, and the lookup table associated with the field (if any). When the user selects the “Save” button, the system changes the database structure of the table, indices, and/or relationships. Selecting the “Remove Tables” menu option displays the “Remove Tables List” form ( FIG. 9A C). When the user selects the “Save” button, the system will delete the tables selected by the user. Selecting the “Remove Fields” menu option displays the “Remove Fields Filter” form ( FIG. 9A D), which allow the user to select the table from which fields will be deleted. When the user selects the “Apply Filter” button, the form in  FIG. 9A E will be displayed.  
         [0052]     The “Remove Fields List” form ( FIG. 9A F) allows the user to specify the fields to be removed from the selected table. When the user selects the “Save” button, the system will change the table structure and remove the selected fields. The system will also remove any indices and relationships associated with the deleted fields. Selecting the “Remove Indices” menu option displays the “Remove Indices Filter” form ( FIG. 9A G), which allow the user to select the table from which indices will be deleted. When the user selects the “Apply Filter” button, the form in  FIG. 9A H will be displayed.  
         [0053]     The “Remove Indices List” form ( FIG. 9A H) allows the user to specify the indices to be removed from the selected table. When the user selects the “Save” button, the system will change the table structure and remove the selected indices. The system will also remove any relationships associated with the deleted indices.  
         [0054]     Selecting the “Remove Relationships” menu option displays the “Remove Relationships Filter” form ( FIG. 9A I), which allow the user to select the table from which relationships will be deleted. When the user selects the “Apply Filter” button, the form in  FIG. 9A J will be displayed. The “Remove Relationships List” form ( FIG. 9A J) allows the user to specify the relationships to be removed from the selected table. When the user selects the “Save” button, the system will remove the selected relationships. The “Upload Application Data” form allows the user to upload electronic information (an Access MDB or text file) which contains information that can be user to ( 1 ) replace the existing application, replace the existing data, append the data to the corresponding tables, or ( 4 ) add new tables to the database. The form also allows the user to upload graphics that will be displayed on the Web pages for the application.  
         [0055]     The creation of a copy of the application data for downloading is illustrated in  FIG. 10 . An application program on the central Web site reads the data dictionary ( 22 ) and creates a Microsoft Access MDB (in the Upload/Download directory)( 23 ) with all of the tables in the application&#39;s database (data dictionary tables are not included). Another program then copies the data from the application&#39;s database to the Access database ( 24 ). The user can then download the Access database.  
         [0056]     Tables in the data dictionary are illustrated in  FIG. 11 . The data dictionary consists of many inter-related tables. They are described below:  
                                       Tables   One record for each - the name of the table, the text to           display on Web forms when referring to the table, the           security level required for user access to the table, etc       Table Types   Categorizes the tables in the application (“primary”,           “detail”, etc.)       Fields   One record for each field in each table - the name of the           field, the text to display on Web forms when referring to           the field, the security level required for user access to the           field, the field type, etc       Field Type   Types of fields in the database (“numeric”, “date”,           “character”, etc.)       Index Type   Type of index for a field (“unique” or “indexed”)       Filter Type   Type of filter for the field on the filter form “number”,           “range”, “word”, etc.       Field Events   Specifies the code to be executed when an “event’ (e.g.,           data changed) associated with the field is “triggered”       Index   One record for each index for each table (name of index,           fields in the index, sorted ascending, etc)       Relationship   One record for each relationship between two tables (names           of the tables, fields in the relationship, type of relationship,           etc.)       Accessible   Security level required to display a table or field (“Read”,           “Update”, “Administer” or “None”)       Relationship   Specifies the which “drill down” buttons are to be displayed       Drill Down   for child tables when a primary record is displayed       Forms   One record for each of the forms used in the “Applications           Maintenance” part of the system (can also be used to           develop forms for an application). Specifies the initial form           to be displayed, the buttons to be displayed, the default sort           order, etc.       Form Fields   One record for each field on a form. Contains the same           fields as the “Fields” table       Child Tables   For forms with child tables, contains information about how           the data in the table is to be displayed, any “filter” informa-           tion for the child table, etc.       Applications   One record for each sample application       Application   One record for each table in each sample application       Tables       Application   One record for each field in each table in each sample       Fields   application                  
 
         [0057]     The foregoing has described the principles, preferred embodiments and modes of operation of the present invention. However, the invention should not be construed as being limited to the particular embodiments described above. The above-described embodiments should be regarded as illustrative rather than restrictive, and it should be appreciated that variations may be made in those embodiments by those skilled in the art without departing from the scope of the present invention as defined by the following claims.