SQL - Primary And Foreign Keys

So if your here on this post you're after understanding the mysteries of Primary/Foreign key relationships. Well let me tell you they are an art form not an exacting science something at first you may not appreciate until you deal with your own database schema's.

Basically, all databases need them. I have had arguments with people in the past saying "you don't need them" I normally let them have just enough rope to hang themselves but make sure I have got the scissors on standby to save the day when they discover the need for them when duplicate orders or duplicate customers start cropping up in thier "brand new" database system.

I cannot stress to you all the importance of primary keys.....foreign keys are important but in my line of work (BI) I can get away without using them as much. But Primary Keys are paramount in a design as they make them unique and indexed. The final point about indexes will be covered in more detail on a separate video as the goal here will be to understand the symbiotic relationship these primary/foreign key elements have for each other.

This is one of many videos which can be seen at PCTeach.me. Come join the gang!

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[wildchild15381]

man, stop talking about access, we are interested just in SQL that's why we are here ;) good tutorial !!

[PCTeachME]

@wildchild15381 Hi sorry I do tend to ramble (was one of my first vids I posted). Glad it helped though ;)

[rabitman3000]

you sound kinda like justin lee collins ;D but thanks for the help

[PCTeachME]

@rabitman3000 Thanks... I think.  I didn't think I sounded like him...although I may look a bit like him minus the beard :)

[TheJondmac]

haha. he sounds like the dog in Family Guy :D

Nice tut anyways.

[PCTeachME]

@TheJondmac Thanks! or should I say Woof Woof :)

[sanwariaamir]

YOU ARE A SAVIOR. Thank you so much for the very informative tutorial.

[PCTeachME]

@rokelly2011 Email on its way with login details. Again, sorry for the mix up!

[PCTeachME]

@rokelly2011 Hi There, I just saw your registration popup. I am having difficulties with my hosting provider regarding email speed. One thing to check is your junk folder as the email may have gone there.  I will however reset your password and email directly. You should expect something in the next 30 mins. Sorry for the mixup. I will delete the other users you have created and you should be good to go.

[rokelly2011]

@PCTeachME PCTeachME hi, I try to register but it doesn't send any password to my email.. I already tried twice, is it the correct website? (h t t p : / / pcteach.me / ) I am currently doing a website using ASP.net Microsoft Visual Web Developer 2010 Express and using SQL Database Server 2008.. I am new to all of these. Need any help.. Thanks.