Access ELF Lexicon Lookup Window

During the Analysis process, Access ELF examines the terms you use in defining fields and tables, and uses its built-in dictionary to try to predict what kinds of synonyms you might use in your queries. You'll probably never notice when Access ELF guesses correctly, since it seems so natural to substitute one word (like "worker") for another (like "employee"). But sometimes Access ELF will misinterpret. That's when you'll need to know how to use the Lexicon Editor.

All the attributes that Access ELF has defined for a given word are visible in the display pane of the Lex Lookup window. Enter the word in the drop-down box, and click the Lookup button. You'll get a listing of the attributes -- for data terms this includes the tables and fields it's contained in.

For instance, typing in Leverling brings up the attributes:
PNoun: DATA CAPDATA NOBLE SINGULARITY EMPLOYEES_ LASTNAME
The last two entries indicate that "Leveling" is a data item of the LASTNAME field of the EMPLOYEES table. (In the ELF system, table and query names are always indicated by a trailing underscore -- this includes the any table names you type in as part of a Phrase definition!) Working backwards, SINGULARITY indicates that this is the one and only occurence of "Leverling" in the database; and NOBLE indicates that "Leverling" is not part of a compound (as for example "Leverling Consulting"). CAPDATA indicates that it is spelled with an initial capital letter; and DATA of course means that it comes from a database field.

When all's well, this information is better kept behind the scenes; but again, when Access ELF makes an improper assignment, you need to know how to repair it. Any attribute assignment can be added to the word currently in the lookup drop-down by typing the attribute into the box below Add Attribute, and clicking the button. To remove an attribute, enter KILL <attribute> where <attribute> is the attribute name.

Because words can have more than one part-of-speech definition, you must make sure that the radio button for the POS you want is selected. So for instance, to remove the DATA attribute from Leverling, you'd select Data, enter KILL DATA, and click Add Attribute. To reset back the way it was, enter DATA, and click again.

Let's back up and do that one again, since it's a little confusing. When a word displays in the Lex Lookup window, it shows its part-of-speech by starting with the POS category followed by a colon. For instance, the "Leverling" entry starts out PNoun: DATA CAPDATA NOBLE etc. Now in most cases this POS category matches the radio button on the panel at the bottom. But somewhere along the line we changed the radio button label for CNoun (Common Noun) to just plain "Noun" and the radio button of PNoun (Proper Noun) to "Data". This was really in order to clarify that the PNoun category includes any type of word which is used as a data entry in your database. For instance, if you've got a field listing the colors Red, Blue and Green, these will all wind up in the ELF Lexicon as PNouns -- not Adjectives!

So in the previous example, selecting the DATA radio button means that the attribute change will be applied to the PNoun definition. And entering KILL DATA means to remove the DATA attribute from this definition.

At least at first, deleting attributes will probably be a more common occurrence, as you try to help Access ELF avoid the pitfalls of its mistakes in interpreting your database design. One of the common problems is when the software guesses that one word should be interpreted as a synonym for another. For example, in the Category table there are entries including "Beverages", "Confections" and "Dairy Products". What if Access ELF were to interpret "Product" as a synonym for "Dairy Product" in the same way that it interprets "Category" as a synonym for "Category Name". Then you would see SYN (Dairy Product) in the definition of "product"; which would probably cause a heap of trouble when you asked questions about "seafood products" and other categories or product. In this case, you could enter KILL SYN, to remove this attribute. Probably even better would be to remove the word as a data entry altogether; after all, why should there be a entry in Northwind for "Dairy Products" when there's no entry for "Seafood Products"? The word "product" is, or should be, implied; here's one example of a tiny inaccuracy in Microsoft's example database.

Now in fact, Access ELF doesn't make this particular error; instead it notices that "product" is more likely to be used in reference to any of the items in this column; and so it marks "product" with the special attribute CATEGORIAL. This means that it probably refers to every member of the category, although it happens to appear only once. It's just a coincidence here that we're talking about the "CategoryName" field as the category; for instance, another example would be the publisher "Random House" appearing in a PUBLISHER category. Here the word "House" would also be marked CATEGORIAL, indicating that ELF will associate it with "Random" only as a last resort; since it's possible to ask questions like "Which publishing houses handle Stephen King?"

What other words in the Northwind database might be defined as CATEGORIAL? This gives us a chance to look at another new feature of release 2.0, the Lex Lookup browse list. Just type CATEGORIAL into the "Browse for this attribute:" box, and press Enter. All the words that share this attribute are listed, for instance "Connection" and "Import". You can double-click a word from this list and immediately see the rest of its definition. (If the word happens to have a synonym definition, the browse list will automatically switch to Synonym mode to show you all the other words that also have that same synonym.)

On very large databases, you may want to switch this "AutoBrowse" feature off, since it may slow down lookups. This option is selectable from the Preferences tab of the Selectable Settings window.

The Lexicon editor will also be useful for adding attributes that define special properties of words. For example, when you ask Who was born in August? you naturally don't mean this August, the way you would when for instance you'd ask "Who bought seafood in August? To distinguish the BIRTHDATE field as one which is queried irrespective of year, we mark it with the attribute BIRTHDAY.

The editor will also let you enter attribute/result pairs in some cases, for example when defining synonyms. Here's an example that also answers a question we hear frequently from our British friends: will Access ELF handle British usages. In general, ELF is geared to American usage, but it's quite easy to use synonym definitions (as well as phrase definitions) to customize its use. If we want to type Who was engaged in August? instead or "hired", we can add the synonym to the lexicon. Type engage into the word box, select the Verb radio button, add syn (hire) into the Add Attribute box and click the Add Attribute button.

This technique also lets us define special properties. For instance, in Worksheet mode we'll often want to "drill down" on a particular field to see details about its associated records. A common use would be to drill down on a Country field to see information listed region by region, or state by state. To do this, we could add drill (state) as an attribute for the field COUNTRY, making sure to select the Noun radio button. Notice that you must select the radio button for the part-of-speech you want to assign to, since Access ELF will add a new entry into the category you've selected if one doesn't already exist. Now when you double-click on a entry in a "Country" column in the Worksheet, Access ELF will automatically run a new query breaking down the answer by state. By the way, nothing prevents you from running these definitions in either direction, for less exact hierarchies. So for instance you could define AUTHOR drill (agent) as well as AGENT drill (author), so you can go from authors to a listing of associated agents, or vice versa, with a simple double-click.

(Note: Beginning with version 3.0, you can do this more simply by connecting any two fields in the Verb Mapper, using the verb "drill".)

It would be nice if you could browse a simple list of attributes that you could change, starting with DRILL and SYN and moving on. We don't want to scare you, but there are currently 256 attributes defined by the ELF engine (although only about 175 of them are predefined on words in the lexicon). For a complete listing see ELF Engine Predefined Attributes. You can easily use the Browse for Attribute feature to see which particular words in your interface have been assigned these attributes.