19 lines
781 B
Markdown
19 lines
781 B
Markdown
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# Single Table Inheritance
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**Summary:** don't use Single Table Inheritance (STI), use separate tables
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instead.
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Rails makes it possible to have multiple models stored in the same table and map
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these rows to the correct models using a `type` column. This can be used to for
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example store two different types of SSH keys in the same table.
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While tempting to use one should avoid this at all costs for the same reasons as
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outlined in the document ["Polymorphic Associations"](polymorphic_associations.md).
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## Solution
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The solution is very simple: just use a separate table for every type you'd
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otherwise store in the same table. For example, instead of having a `keys` table
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with `type` set to either `Key` or `DeployKey` you'd have two separate tables:
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`keys` and `deploy_keys`.
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