Method and apparatus for access, integration, and analysis of heterogeneous data sources via the manipulation of metadata objects

Abstract

A computer-based method represents a subset of a dataset table of rows and columns. The method includes selecting a set of blocking variables corresponding to blocking columns of the dataset table. For each row in the dataset table, a tuple of values for the blocking columns uniquely identifies the row within the dataset table. The method also includes selecting a set of non-blocking variables that correspond to columns of the subset. The set of non-blocking variables does not intersect the set of blocking variables. The method also includes creating a block information structure that includes both the set of non-blocking variables and, for each blocking variable in the set of blocking variables, a set of values.

What is claimed is:  
     
         1 . A computer-based method of representing a subset of a dataset table of rows and columns, the method comprising: 
 selecting a set of blocking variables corresponding to blocking columns of the dataset table such that, for each row in the dataset table, a tuple of values for the blocking columns uniquely identifies the row within the dataset table;    selecting a set of non-blocking variables corresponding to columns of the subset, the set of non-blocking variables disjoint from the set of blocking variables; and    creating a block information structure that includes the set of non-blocking variables and that includes, for each blocking variable in the set of blocking variables, a set of values.    
     
     
         2 . The method of  claim 1 , wherein for each row in the subset having a tuple of values for the blocking columns, the values of the tuple are included in the corresponding sets of values for the blocking variables.  
     
     
         3 . The method of  claim 1 , wherein the subset of the dataset table includes the entire dataset table.  
     
     
         4 . The method of  claim 1 , wherein a sum of the number of elements in the set of non-blocking columns and in the sets of values for the blocking columns is linearly proportionate to an upper bound on binary storage requirements of the block information structure.  
     
     
         5 . The method of  claim 1 , further comprising: 
 storing the block information structure on a machine-readable medium.    
     
     
         6 . A computer-based method of accessing information in heterogeneous databases, the method comprising: 
 presenting a graphical user interface with controls representing a data cart and a plurality of datasets;    receiving user input that selects a dataset to add to the data cart from the plurality of datasets;    generating a block information structure specifying the dataset; and    adding the block information structure to the data cart.    
     
     
         7 . The method of  claim 6 , wherein specifying the dataset includes incorporating into the block information structure a set of non-blocking variables, a set of blocking variables, and for each such blocking variable, a set of values.  
     
     
         8 . The method of  claim 7 , wherein the dataset includes a plurality of rows, each identified by a corresponding tuple of values from the sets of values for the blocking variables.  
     
     
         9 . The method of  claim 7 , further comprising: 
 for a blocking variable in the set of blocking variables, presenting enumeration controls in the graphical user interface, each corresponding to an existing value in the dataset for the blocking variable.    
     
     
         10 . The method of  claim 6 , further comprising: 
 collecting user input specifying a subset of the dataset, and representing the subset in corresponding block information structure.    
     
     
         11 . The method of  claim 6 , further comprising: 
 saving the data cart to a persistent storage medium.    
     
     
         12 . The method of  claim 6 , further comprising: 
 adding a second block information structure to the data cart, in response to user input.    
     
     
         13 . The method of  claim 6 , wherein the controls representing a data cart include a symbol of a shopping cart.  
     
     
         14 . A computer-based method of retrieving information represented by a blockset, the method comprising: 
 for each of a plurality of blocks in the blockset in which each block specifies a subset of a dataset stored in a database, connecting to the corresponding database, wherein the blockset has a plurality of blocking variables, and the blocks each include a set of non-blocking variables, and specifying includes having a set of values for each blocking variable in the plurality of blocking variables;    adding to a derived table a blocking column for each blocking variable in the set of blocking variables;    adding to the derived table a non-blocking column for each element in a union of the non-blocking variables in the plurality of blocks;    adding a row to the derived table including a cell for each column in the derived table, the row uniquely identified by a tuple of values from the sets of values for the blocking variables; and    populating a cell of a non-blocking column in the row, using a value retrieved from the database corresponding to the block, wherein the block contains the non-blocking variable corresponding to the non-blocking column.    
     
     
         15 . The method of  claim 14 , further comprising: 
 adding a row for each tuple of values from the sets of values for the blocking variables, wherein the tuple occurs in at least one dataset corresponding to a block in the plurality of blocks.    
     
     
         16 . The method of  claim 14 , wherein connecting includes using each block as a basis for a database query that specifies the corresponding subset.  
     
     
         17 . The method of  claim 16 , wherein the database query uses Structured Query Language.  
     
     
         18 . A computer-based method of representing a table derived from a blockset, the method comprising: 
 outputting blockset metadata describing the blockset, including fields for a blockset title and a blockset description;    for a column in the table, outputting column metadata describing a variable associated with the column, wherein the variable is associated with an underlying dataset that provides data to the table in the blockset, and the column metadata includes fields for a title of the variable and for a title of the underlying dataset.    
     
     
         19 . A computer-based method of collecting metadata for a dataset, the method comprising: 
 prompting a user to provide a database name;    confirming that the database name represents a database;    displaying a list of tables in the database to the user;    receiving user input specifying a table in the list of tables;    prompting the user to confirm that a list of blocking variables and a list of non-blocking variables are correct for the database;    prompting the user to confirm metadata for the dataset and for the list of non-blocking variables;    if the user confirms the list of blocking variables, the list of non-blocking variables, and the metadata, adding a dataset corresponding to the table to a collection of datasets.    
     
     
         20 . The method of  claim 19 , wherein the metadata includes a title for the dataset.  
     
     
         21 . The method of  claim 19 , wherein the metadata includes a description for the dataset.  
     
     
         22 . The method of  claim 19 , wherein the metadata includes a title for a non-blocking variable in the list of non-blocking variables.  
     
     
         23 . The method of  claim 19 , wherein the metadata includes a description for a non-blocking variable in the list of non-blocking variables.  
     
     
         24 . An article comprising a machine-readable storage medium that stores executable instructions to represent a subset of a dataset table of rows and columns, the instructions causing a machine to: 
 select a set of blocking variables corresponding to blocking columns of the dataset table such that, for each row in the dataset table, a tuple of values for the blocking columns uniquely identifies the row within the dataset table;    select a set of non-blocking variables corresponding to columns of the subset, the set of non-blocking variables disjoint from the set of blocking variables; and    create a block information structure that includes the set of non-blocking variables and that includes, for each blocking variable in the set of blocking variables, a set of values.    
     
     
         25 . An article comprising a machine-readable storage medium that stores executable instructions to represent a subset of a dataset table of rows and columns, the instructions causing a machine to: 
 present a graphical user interface with controls representing a data cart and a plurality of datasets;    receive user input that selects a dataset to add to the data cart from the plurality of datasets;    generate a block information structure specifying the dataset; and    add the block information structure to the data cart.