1. A method for detecting one or more subject columns of a table, the method comprising: selecting a specified number of columns from the table as candidate subject columns, each candidate subject column being a candidate for a true subject column of the table, each candidate subject column including a plurality of values; for each candidate subject column: determining a co-occurrence for values in the candidate subject column, including determining how often values in the candidate subject column also occur in true subject columns in a plurality of other tables; calculating a score for the candidate subject column based on the determined co-occurrence, the calculated score indicating a likelihood of the candidate subject column being a true subject column; and classifying the candidate subject column as one of: a true subject column of the table or a non-subject column of the table based on the calculated score for the candidate subject column.
1. A method for detecting one or more subject columns of a table, the method comprising: selecting a specified number of columns from the table as candidate subject columns, each candidate subject column being a candidate for a true subject column of the table, each candidate subject column including a plurality of values; for each candidate subject column: determining a co-occurrence for values in the candidate subject column, including determining how often values in the candidate subject column also occur in true subject columns in a plurality of other tables; calculating a score for the candidate subject column based on the determined co-occurrence, the calculated score indicating a likelihood of the candidate subject column being a true subject column; and classifying the candidate subject column as one of: a true subject column of the table or a non-subject column of the table based on the calculated score for the candidate subject column. 6. The method of claim 1 , wherein determining a co-occurrence for values in the candidate subject column comprises calculating a co-occurrence fraction for each value in the candidate subject column, the co-occurrence fraction indicative of how often the value occurs in true subject columns of the plurality of other tables relative to how often the value occurs overall in the plurality of other tables.