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2_Primary_key_presentation_l2_v2.pptx
Primary key
What do you remember from previous lesson?
Primary key
Use
examples
Key words
Very often, PK is used as an item (or people’s) ID, because it can’t be repeated or null. To easily find PK in table it’s better to look at field’s name analyze it.
PK and FK
Primary key is not a Foreign key.
Primary key needs to make all records identical, when FK is needed to connect two tables with some field.
Video watching
https://www.youtube.com/watch?v=7_9Jb9Fi9nI
Fill out the table:
Primary key | Unique key |
Thanks for the attention!
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