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The sdssQA is a downloadable Java application which provides a GUI that allows users to directly connect to and query the SDSS databases using SQL. It runs on Unix, Linux, Windows, and Mac. It is available for download at this location. This page provides download, installation, and usage instructions.
Downloading and Installing the sdssQA
The sdssQA is a standalone Java application, which you download as a single .jar file. In order to use the sdssQA, your system must have Java (version 1.4 or higher) installed; this can be downloaded from the Sun website.
Two directories are created in the user's home directory:
When you start the sdssQA, a window with three panes will appear. A miniature is shown below, with the panes labelled by their names. When the QA is first opened, the Results Pane may not exist, but it appears as soon as the first query is executed.
The Main sdssQA Window
The three panes are:
All of these panes can be either resized or closed using the pane dividers. The latest version of the QA implements "tabbed" windows. When a window is minimized, it appears as a tab at the top of the results pane. When a new window is opened, it appears as a new window on top of the already existing windows, with its own tab. Clicking on the tab for a window will bring it to the front.
Entering, Starting, and Stopping Queries
There are three ways to enter queries into the sdssQA:
Once a query is loaded, you run it by pressing the green arrow button, or by selecting Query -> Execute from the main menubar. When the query is running, the bottom of the Query Pane will flash the word 'Running', and output will display in the Results Pane. The green arrow will turn into a red square , which can be used to stop (abort) the query. You can also select Query -> Cancel from the main menubar to stop query execution. When the query is done (or aborted) the bottom of the Query Pane will say 'Ready'.
Saving Queries and Query Output
You can save both the SQL Query and the query output. First, we discuss saving the output (or results) of your query.
You select the output type when you save the query results. You can save the results by either:
These will bring up a window where you can select the destination directory, the output type (csv or xml), and the output filename.
Changing Servers and Databases
A variety of databases are available to QA users. You can select which server to connect to, and which database to use from that server. Using the Options->Config menu item, and clicking on the Servers tab, allows you to enter the URL of a server you wish to connect to. Just type in the URL, and click 'Add'. If it is a valid URL, the available databases from that server will appear in the right pane of the window. You can select one of those databases and make it your default database for future query windows by clicking the checkbox marked 'Default?'.
The Configuration Window
Modifying sdssQA Configuration
The Options->Config menu item brings up a window (shown above), where you can select databases and modify the behavior of the sdssQA. You can do the following: