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(Continued from page 5) Once the query has been set up, you can click
the View button in the ribbon to see the results
ships between records in different tables and as a data table. Note there are various selec-
there’s no SQL support. tion criteria defined so that we only get the set
of rows that we’re interested in.
“Flat File” Database Programs
Commercial database programs like MS Ac-
cess, Word Perfect Paradox (formerly a Bor- The equivalent Structured Query Language
land product) and Apple FileMaker are more (SQL) statement would look like this: SELECT
full-featured database tools with true relational DISTINCT SCSCA_Number, Last_Name,
support and SQL support. These tools can be First_Name FROM ClassSignInList WHERE
used to build relatively sophisticated applica- ((Last_Name<>"Guest") AND (Valid=Yes) AND
tions with complex relational data structures, (Event_ID="SI0BC097B") AND
input forms, result viewers and printable re- (Signin_Date>=#1/1/2017#)) ORDER BY
ports. However, these commercial tools aren’t Last_Name, First_Name;
free and take some serious time to learn.
The SELECT DISTINCT tells the database en-
On a local area network, these commercial gine to only return each unique attendee once,
tools support multiple concurrent users via “file no matter how many times that person attend-
server” locking technology. Each user is run- ed the SIG. Here’s a display of the results of
ning their own copy of the database “engine” running the SELECT query. I’ve intentionally
to do reads, inserts, updates and deletes, blurred the results.
which can lead to access contention. Perfor-
mance can become an issue if there are more
than a few concurrent users accessing the da-
tabase file(s).
Here’s an example of the MS Access visual
query designer, setting up a query to retrieve a
list of club members who attended at least one
session of the Internet Investing SIG since
January 2017.
I use MS Access and its databases (along with
the VB.Net programming system) for the Com-
puter Club’s membership roster and the event
sign-in systems and it has worked very well in
those contexts.
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