The Qddb Database Suite
Now, that you know how to perform simple searches, you may want to add or omit certain fields from your results. By default, nxqddb displays only the first five fields in the search results window.
If you click the Configure menu button, you will notice many configuration options. This is the current state of all your nxqddb settings. The search results configuration (see Figure 3) determines what fields are present in the search results, how those fields are displayed, and in what order. You can also add user-defined columns to the search results.
After configuring the search results, you may choose to save the configuration. nxqddb recognizes two configurations on startup: the global configuration and the personal configuration. The global configuration is the default for any user of a particular database. The personal configuration overrides any global settings for an individual user.
While the simple search mechanism is extremely handy for quick lookups, it cannot perform all types of searches. The expert search is designed to handle generic searches and includes the ability to save the search criteria for later use. Figure 4 shows the expert search window. From this window, you can combine and nest queries in any way you like. Ranges use two entry boxes; other search types use only the leftmost entry.
Suppose you want to find all the primary renters whose lease expires this month. The idea is to provide a list of the search criteria to the expert search engine. Our search then should be all Apartments.Person.PrimaryRenter == “Y” and Apartments.Lease.End == “@firstofmonth(this month)-@lastofmonth(this month)”.
The expert search window always contains at least one field for search criteria. To restrict our search to the particular fields specified above, we click the down arrow next to the entry box, choose Apartments.Person.PrimaryRenter as the attribute name and dismiss the pull-down menu, then type Y in the entry. Now we have to specify a second criterion, so we:
Click the Append Node button to add a new entry.
Click the down arrow to select a date range search on the Apartments.Lease.End attribute.
Dismiss the menu.
Type @firstofmonth(this month) in the left entry and @lastofmonth(this month) in the right entry.
Now, we can click the Search button, and we will see a search results window that contains all the matching rows using the current search results format.
Ad-hoc reports can be easily produced by executing these two steps:
Configuring the search results.
Performing a simple or expert search.
More detailed reports require the Qddb report generator. The Qddb report generator can produce postcards, letters, e-mail, summaries of numeric fields, graphs, bar charts and tables. The basic idea is the same as producing an ad-hoc report, but you generally want to save the settings for both the search criteria and results format for later use.
Figure 5 shows the report generator's main window. From this window you can define multiple expert searches and a search results configuration. After defining what you want to see and how you want to see it, you can choose any combination of the six output formats.
For example, suppose we want to send a postcard to each renter whose lease expires this month. First, we need to configure the format of our return and destination addresses. Choose the Report Format Defaults option under the Configure menu button. You will notice two options in the cascaded menu: Return Address and Destination Address. Choose Return Address and fill in the return address as you want it to appear on postcards and letters. Next, choose Destination Address. This option will format arbitrary fields for the destination address on all postcards and letters. Once you have configured the addresses, you may wish to save your configuration so these options become the default.
We have already seen how to perform the expert search, so let's just use the previous example for defining what you want to see in your report. Next, we have to define the relevant fields for the report via the Results Format button. To generate a postcard, we must include all address information, plus we probably want to include the lease's expiration date for inclusion in the message. Now, we can choose the type of reports we wish to generate. If you want a listing as well as postcards, you can choose both options and click the Run Report button. Since we chose listing as well as postcards, the listing appears first and can be printed out. After printing the listing, we are prompted for the postcard message as shown in Figure 6. Notice that the postcard message is personalized for the recipient by using data from each record.
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