10. A method, implemented at a computer system that includes one or more processors, for linking a child table to a parent table in a database system using a foreign key in the child table, the method comprising: identifying a semantic expression associated with a row of the parent table, the semantic at least: being stored as a first key in the row of the parent table; describing a semantic relationship using association criteria; referencing a second key from the row of the parent table; and receiving as input a foreign key from the child table; for each row of a plurality of rows of a child table, performing the following: evaluating the expression against a foreign key of a child table row for satisfaction of the semantic expression, wherein satisfaction of the semantic expression occurs when the foreign key of the child table satisfies the semantic expression, rather than by direct equality to the semantic expression; and based at least on the foreign key of the row satisfying the semantic expression, creating an association between the foreign key and the row of the parent table.
10. A method, implemented at a computer system that includes one or more processors, for linking a child table to a parent table in a database system using a foreign key in the child table, the method comprising: identifying a semantic expression associated with a row of the parent table, the semantic at least: being stored as a first key in the row of the parent table; describing a semantic relationship using association criteria; referencing a second key from the row of the parent table; and receiving as input a foreign key from the child table; for each row of a plurality of rows of a child table, performing the following: evaluating the expression against a foreign key of a child table row for satisfaction of the semantic expression, wherein satisfaction of the semantic expression occurs when the foreign key of the child table satisfies the semantic expression, rather than by direct equality to the semantic expression; and based at least on the foreign key of the row satisfying the semantic expression, creating an association between the foreign key and the row of the parent table. 13. The method in accordance with claim 10 , the foreign key being tokenized text.