Creating an Erntity-relationship diagram (ERD).

According to this prompt on Linked In, this Monday Morning I’ve been selected to write an article on creating an Entity-relationship diagram (ERD). OK – lets dust off the college text book and go through the steps to model the relationships between entities in a database.  Linked In has a 750 char limit, and only let me post three times about ERD's breaking this up, so - I moved the whole 3000 character doc out here to my blog!

Generally speaking – and there’s many database specific variants, you will need to Identify Entities. Start by identifying all the entities within the system you're modeling. Things. Nouns. (Person, Place, Paint Color, Family Size, etc. Entities are typically nouns representing objects, concepts, or things about which data is stored.

Next, you need to review each noun (entity) and Define the Attributes. Every entity is going to have descriptive characteristics that identify and define its attributes. You will represent these attributes as columns in a database table – a list of colors, regions or states in a country.

Now, with your entities and attributes, you Determine Relationships. Identify how the entity relates to it’s attribute. Can a car have one color? Or many colors? Relationships define how entities interact with each other. You can look at these as verbs – has, lives, is, contains, etc.

A bit more specificity to your verbs (relationships) – what is the cardinality of each relationship. Cardinality describes the relationships between entities, such as one-to-one, one-to-many, or many-to-many. As above – can a car have one or many colors? Would a person live in one, or many states. Would many cars have the same color?

Ok – thinking part is over; now we draw! Using tools specific to your database, or one of many online or paid tools, Draw the ERD. There are standard notations to use like Crow's Foot notation and Chen notation. Choose one that suits your preference or organizational standards. Specific directions will vary by tool, but the general steps are to:

1. Create Entity Boxes: Represent each entity as a box in the diagram. Label the box with the entity name and list its attributes inside the box.
2. Add Relationship Lines: Draw lines between related entities to represent the relationships. Label each line with the appropriate relationship type and cardinality.
3. Refine the Diagram: Review the diagram to ensure it accurately represents the relationships and attributes of the entities. Make adjustments as necessary to clarify the structure.
4. Document the ERD: Document the diagram to provide additional context and explanation. Include a legend that explains the notation used, as well as any assumptions made during the modeling process.

And the most important part – none of this takes place in a vacuum. Review and Validate the ERD with stakeholders, subject matter experts, or other team members to validate its accuracy and completeness. Make revisions based on feedback as needed.

There you go, LinkedIN and followers – a basic document on creating Entity Relationship Diagrams. Enjoy!

Will England

closing out the weekend. what comes next?

Too rainy and cloudy to get out to see the lunar umbral eclipse. At least the weather is passing. Been an enervating two days - weather changes, so on.

Come Monday, I meet my new boss, in my new organization, with a complete different set of expectations and performance goals. One's I was not aware of, and haven't met. But we shall see what come to pass tomorrow.

Haven't been feeling well at all. Internalized the environment and the unknown generating a good case of the ooogies. (technical term).

This too shall pass and we will all learn some Darshan lesson from the experience. Until then,

Namaskar! 

16 March 2024 moment.

Glad there's something good to close out the weekend. Been feeling like hammered pooo all day. I was going to get the hoses set back up to water in Fertilizer and seed here and at mom's. Glad I didn't - hard freeze forecast for tonight.

Such is the way of the world. Tomorrow is a new day and a new chance to get needful things done.

This Weekend

 

A good weekend. Got taxes sorted - found a user error that would have cost me $2K. Filed taxes for a refund, even with all the layoff, severance, etc. Started watching 'Constellation' on AppleTV (thanks, T-Mobile, for the free subscription). Interesting enough to keep the attention. 

 

Didn't get out on the bike even though the weather was excellent; spent too much time glaring at the screens while working on taxes.

 

This week - no appointments, but Friday and Saturday are pistol competitions, one indoor and one outdoor. Going to see if I can make at least one of them. Been too long since I've done any timed shoot-move events. Definitely time to move more!

Shooting at the Super Bowl Victory Parade

Not the day we expected. 61, sunny, Kansas City Chiefs celebration of their Super Bowl win with a parade and a million fans.

As it ended, shots rang out from one or more groups. Near 2 dozen injuries, one fatal. Some of the shooters may have been stopped by visiting fans from Wichita and Nebraska.

News is disjointed - the internet turns all stories into an echo chamber, regurgitating hours old data as breaking news. 

Many of the wounded were children. All of the children are stable and should physically recover soon. At least one adult is in critical condition. 

Three suspects were taken into custody. Nothing is known for the motives or even if there was one, two or even a third shooting this afternoon. We simply wait for the police to sort out the connections, while we are beaten with politics blaming the race, blaming the gun, blaming the political party running Kansas City, MO. 

So, we wait. 

Assign data elements to Analytics variables using Adobe Tags Rules.

Been working on this for half the day.  Finally sorted it out.  If you are using Adobe Tags, formerly Launch, and want to add your Adobe events, eVars and Props using the GUI pulling directly from your adobeClientDatalayer, you use Global Variables in the Adobe Analtyics Extension for page  level variables.  

For other variables, not set every page load, you create rules.  You don't need an event or condition, just an action.  Click the 'Add' button at the bottom to define the action.

Create Rule, setting the Action to capture Adobe Variable

Configure the action for the rule, setting the eVar or Prop to a data element defined previously

From the Adobe documentation:

Set variables in rules

Variables set in rules are ideal in cases where you don’t want variables set on every page. You define the criteria in the rule. See Rules in the Adobe Experience Platform tags documentation.

1. Log in to Adobe Experience Platform Data Collection using your AdobeID credentials.
2. Click the desired tag property.
3. Click the Rules tab, then click on the desired rule (or create one).
4. Click the Add button under Actions.
5. Set the Extension drop-down list to Adobe Analytics, and the Action Type to Set Variables.
6. Click the  icon to the right of the desired Analytics variable. Your organization’s solution design document dictates what Analytics variable to use.
7. Select the desired data element in the modal window. Click Select.
8. The data element name is added to the text field surrounded by % signs. For example, if you named your data element “Page name”, you would see the string %Page name% when assigning a data element to a variable.

 

Note - setting the variable in the rule does not send the beacon sending the data to Adobe.  You still need to create a final rules to trigger the becaon, one for page load (s.t()) and one for event (s.tl()).  That's beyond the scope of this post.

What makes good motorcycle gear?

 

What makes good gear?

Helmet - Full face, FITS your head, DOT certified. Snell is good too, but those are more expensive. Not optional.

83MPH into the pavement. Walked away.

Jacket - thicker cordura (1050 on the impact points), or leather (fold it in half on the sleeve - is it at least 2mm / 3/16th of an inch thick folded?) ECE certified armor in the elbows, shoulders, FITS and is comfortable. Not optional.

Gloves - solid leather that FIT and have retention - even just the pull string on work gloves is better than elastic. Not optional.

Over the ankle leather boots or solid leather high-tops, tied securely. Not pull on cowboy or engineer boots. Impact armor on the ankle bone if you get moto specific boots.

Pants - Jeans do work, but plan on eventually getting cordura or leather riding pants. Again, thicker is better, as long as it's comfortable, FITS and has ECE armor on the impact points.

Full cordura amored gear.  83MPH into the pavement. Walked away.