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61 lines
1.2 KiB
61 lines
1.2 KiB
# Nesting Models
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## Objectives
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Currently, we only have two unrelated models: people and locations. Let's add the functionality so that whenever we have JSON that represents a person, it will contain a `home` property, which is the associated `location` object:
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```JSON
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{
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"id":4,
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"name":"Bob",
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"age":25,
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"home": {
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"id":2,
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"street": "123 Fake Street",
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"city": "Aurora",
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"state": "NY"
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}
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}
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```
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Also, when we have a location, it will contain an array of people objects:
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```JSON
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{
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"id":2,
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"street": "123 Fake Street",
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"city": "Aurora",
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"state": "NY",
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"inhabitants":[
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{
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"id":4,
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"name":"Bob",
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"age":25
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},
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{
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"id":7,
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"name":"Sally",
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"age":74
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},
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]
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}
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```
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This will be a one-to-many relationship
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## Add home_id to people
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First, go into `psql` and add a `home_id` INT column to the `people` table:
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```sql
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ALTER TABLE people ADD COLUMN home_id INT;
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```
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Now we can give people homes like so:
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```sql
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UPDATE people SET home_id = 2 WHERE id = 4;
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```
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The previous code will find the row with an `id` of 4 and set the `home_id` column to 2;
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