Lecture 17MySQL

Tables and Relations 101

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* Course logo spider web photograph from Morguefile openstock photograph by Gabor Karpati, Hungary.

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Review – Starting Servers

3/7/17 Slide 2CSU CS CT 310 - Web Development, ©Ross Beveridge & Jamie Ruiz

Keep in mind MySQL works through a client-server interface to a separate database server process/machine.

Data - Tables

ØTable is, more or less, a flat database.

ØContains “things”, objects.ØOne thing per row.ØColumns store attributes.ØPrimary index unique for each row.ØRelations kick in later

ØHow we relate tables to one another.

3/7/17 Slide 3CSU CS CT 310 - Web Development, ©Ross Beveridge & Jamie Ruiz

Exercise Some Commands

Ø use

Ø CREATE

Ø INSERT

Ø SELECT

Ø UPDATE

Ø DROP

3/7/17 CSU CS CT 310 - Web Development, ©Ross Beveridge & Jamie Ruiz Slide 4

cd_id name artist

1 Mudlark Leo Kottke

2 My Feet Are Smiling Leo Kottke

3 Lucky The Man Wizz Jones

4 The Blue Idol Altan

5 Return of the Repressed John Fahey

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Create Music Database

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In general, new databases do not come and go often.

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Example 1

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Where’s the Beef, ah … Data.

Ø Data from tables is stored in files.Ø Case sensitivity comes from host OS.Ø In case it is not obvious.

Ø NEVER MANIPULATE THESE FILES DIRECTLY.

3/7/17CSU CS CT 310 - Web Development, ©Ross Beveridge & Jamie

Ruiz Lecture 18, Slide 7

Relations 101

ØLeo Kottke appears twice.

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Leo Kottke Wizz Jones Altan John Fahey

Mudlark

Lucky The Man

Return of the Repressed

The Blue Idol

My Feet Are Smiling

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Example 2

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Keys: Primary and Foreign

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Primary Key Unique!

Establishes Relation:Loosely speaking, a ‘pointer’ to the other

object.

Two cdsrelated to one artist.