Help for Simple Query pages

This page provides an overview of information on the SimpleQuery/TableViewer tool. Additional information on specific fields is available by clicking on the text labels for a field.

Query Page

On the query page you can specify the central position and radius of a region to be searched. The position may be given as a target name or in J2000 coordinates.

If called without an specific resource specified, a third input field is present where a knowledgeable user can specify the IVO Identifier of the resource to be queried. Normally this service should be invoked with the resource specified, but this mode allows is useful for debugging.

The results page

The query results are downloaded and presented to the user in an HTML table. Users can scroll through, sort, filter, select and propogate results.

Scrolling through results

The table results are scrolled using the page controls to the top right of the form. You can select the next or previous page, or a specific page number. The number of results displayed per page can be changed.

Sort

Just click on a column heading to sort a table by that heading. The first time the sort order is ascending; a second click on the same column header will start a sort in descending order. An arrow will appear in the header to show the current sort column. Note that the entire table will be resorted, not just the rows currently being displayed.

Filter

Enter a constraint in the box at the top of a column to filter the table on that column. E.g., if you want only the exposures greater than 100000, enter >100000 in the box. As soon as you move out of the box the table will be filtered. Only fairly simple sorts are supported. >, >=, <= < can be used with numeric columns as well as a range operator "..", e.g., 1000..2000 to get everything between 1000 and 2000 inclusive. If no operator is specified '=' is assumed.

For character columns only fairly limited matches are supported. A string column defaults to matching all rows that begin with that start with that string. If a '*' is included in the string, it will match any set of characters (including none). E.g., 3C*273 matches '3c273' and '3C 273'. Character matching is case insensitive. The '=' may be used to request an exact match rather than a starting with. E.g., =White matches White but not Whiteside while White would match both.