• List of currently supported features, including known bugs

• This is the best place for a new user to start.

• It provides access to sample applications including schema, data, and queries.

• Clicking a button to load sample data erases the existing database if there is one, creates sample tables, and populates them with initial data. (WARNING: any existing tables and data will be erased!) Once the data is loaded, sample queries for it appear in the other box.

• Clicking on one of the sample queries transfers back to the Home tab with the clicked-on query placed in the query box. The query is not executed until the “Execute” button is pressed.

• This is the best place to start on an existing database.

• It shows the current tables in the database, including their relation-level lineage relationships (which tables were derived from which others).

• Clicking on a table T transfers back to the Home tab and executes “View Table T” to display the contents of the table.

• This tab also includes a Query box. Entering a query or command and clicking the “Execute” button executes the command and transfers back to the Home tab to show the results.

• This is the best place to start if you’re working on your own database.

• It allows you to load files into scripts. Once loaded, clicking a command in the script transfers back to the Home tab with the clicked-on command placed in the query box. The command is not executed until the “Execute” button is pressed.

• Commands in script files must be separated by semicolons. Blank lines and lines beginning with “–” (for comments) are ignored. Here is a sample script.

• This is the main tab, used primarily for entering queries or other commands into the Query box, executing them (”Execute” button), and browsing query results.

• Note that a “create table T as...” query does not display results. Rather, it creates a table T that now appears in the Schema tab and in the View Tables menu. To see the results, select T from the View Tables menu, or visit the Schema tab and click on T.

• Other features under the Home tab include logging out (with or without deleting the current user), selecting a table to view, and selecting recent commands to be re-inserted into the query box.

• Trio’s query language, TriQL, is described in detail in the TriQL Language Manual. The currently supported subset of TriQL is described here. (See also some planned upcoming features.)

• The query box also accepts DDL and data modification commands. These commands are not documented in the TriQL language manual but you can easily learn them from the sample script. The DDL and Insert commands currently supported are described here. (See also some planned upcoming features.)

This is the richest and potentially most confusing part of the interface. Here are some of the features, separated into data and lineage:

• BLUE TABLES have no uncertainty, so they look like regular relations.

• GREEN TABLES
  • Alternatives - Tuples shaded in “3D” indicate that there are multiple alternatives for (i.e., uncertainty about) the tuple’s value. Click on the tuple to display the alternatives, and click again to “fold” the tuple back to 3D. When folded, the the vertical bars indicate alternative possible values for attributes, but note the tuple must be unfolded to see the exact alternatives for the entire tuple, since not all combinations of attribute alternatives may be present.
  • Question marks - indicate uncertainty about a tuple’s presence.

• ORANGE TABLES
  • Alternatives - same as for green tables.
  • Confidence values - The number in the orange box is the confidence value for an entire tuple (if the tuple is folded, or if it only has one alternative), or for a tuple alternative (if the tuple is unfolded). If there’s a “conf” link instead of a value, clicking the link will cause the system to compute the confidence value. If there’s a “CONF-ALL” link next to the table heading, clicking that link will cause the system to compute confidence values for the entire relation.

• The blue down-arrow buttons are for lineage tracing. (Lineage is traced at the granularity of alternatives, so folded tuples must be unfolded to get the buttons.) Clicking on the lineage button for tuple T shows the tuples (alternatives actually) in T’s immediate lineage.

• Lineage tuples separated by double horizontal bars indicate disjunction (”or”); otherwise, lineage is conjunctive (”and”).

• If any of the lineage tuples are from derived tables, they have lineage buttons for tracing further down.

• Table names above lineage tuples can be clicked to view the table contents.

• Clicking a blue up-arrow button removes the displayed lineage.

• Lineage-tracing buttons are provided for all derived tables and all query results. (If a tuple in a derived table or query result has no lineage, clicking the lineage button on that tuple has no effect.)