comment on

I think there is an easier way to visualize it. Tables don't contain other tables. A table is like a piece of paper. If you were to manually write out what a relational database does, you would be looking at three pieces of college ruled paper side by side.


                    band_members
#############################################################
ID  First Name                Last Name
############################################################
1.  Paul                      McCartney
2.  Ringo                     Starr
3.  George                    Harrison
4.  John                      Lennon


             band_members_and_Bands_linking_table
###########################################################
band_members_id                  bands_id
###########################################################
1                                1
2                                1
3                                1
4                                1
3                                2
4                                3
1                                4
1                                5
4                                5
3                                5


                    Bands
#########################################################
ID  Band Name
########################################################
1.  Beatles
2.  Traveling Wilburys
3.  Plastic Ono Band
4.  Wings
5.  Solo
[download]

That is pretty much it. If this example is any good, you are already visualizing and tracing the relationships between the data.

SQL is fun to learn, because there are only three commands. select, delete, and insert. There is 'update' if you really want to get fancy and combine delete and insert into a single statement. I would not try to Perl and SQL at the same time. I recommend the Head First SQL book, that will probably teach you all you want to know, if you want to go further, I like the MySQL certification book. You could combine those three tables into one, but this style is preferred, because it ~~makes it harder to learn and raises the barrier to entry for Database Administrators.~~ enhances performance

In reply to Re: OT: SQL and me by trippledubs
in thread OT: SQL and me by Lady_Aleena

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