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fix wrong code in polymorphic-associations.md #780

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fix wrong code in polymorphic-associations.md #780

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22 changes: 11 additions & 11 deletions docs/associations/polymorphic-associations.md
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Original file line number Diff line number Diff line change
Expand Up @@ -34,11 +34,11 @@ abstract class AbstractComment<Attributes, CreationAttributes> extends Model<
> {
declare id: number;

@Attributes(DataTypes.STRING)
@Attribute(DataTypes.STRING)
@NotNull
declare content: string;

@Attributes(DataTypes.INTEGER)
@Attribute(DataTypes.INTEGER)
@NotNull
declare targetId: number;
}
Expand Down Expand Up @@ -72,17 +72,17 @@ This solution only requires a single table, to which we add multiple, mutually-e
class Comment extends Model<InferAttributes<Comment>, InferCreationAttributes<Comment>> {
declare id: number;

@Attributes(DataTypes.STRING)
@Attribute(DataTypes.STRING)
@NotNull
declare content: string;

@Attributes(DataTypes.INTEGER)
@Attribute(DataTypes.INTEGER)
declare articleId: number | null;

@BelongsTo(() => Article, 'articleId')
declare article?: Article;

@Attributes(DataTypes.INTEGER)
@Attribute(DataTypes.INTEGER)
declare videoId: number | null;

@BelongsTo(() => Video, 'videoId')
Expand Down Expand Up @@ -111,23 +111,23 @@ In this type of polymorphic association, we don't use foreign keys at all.
Instead, we use two columns: one to store the type of the associated model, and one to store the ID of the associated model.

As stated above, we must disable the foreign key constraints on the association, as the same column is referencing multiple tables.
This can be done by using the `constraints: false`.
This can be done by using the `foreignKeyConstraints: false`.

We then use [association scopes](./association-scopes.md) to filter which comments belong to which models.

```ts
class Comment extends Model<InferAttributes<Comment>, InferCreationAttributes<Comment>> {
declare id: number;

@Attributes(DataTypes.STRING)
@Attribute(DataTypes.STRING)
@NotNull
declare content: string;

@Attributes(DataTypes.STRING)
@Attribute(DataTypes.STRING)
@NotNull
declare targetModel: 'article' | 'video';

@Attributes(DataTypes.INTEGER)
@Attribute(DataTypes.INTEGER)
@NotNull
declare targetId: number;

Expand Down Expand Up @@ -156,7 +156,7 @@ class Video extends Model<InferAttributes<Video>, InferCreationAttributes<Video>
foreignKey: 'targetId',
// highlight-start
// Foreign Keys must be disabled.
constraints: false,
foreignKeyConstraints: false,
// This scope ensures that loading the "comments" association only loads comments that belong to videos.
scope: {
targetModel: 'video',
Expand All @@ -174,7 +174,7 @@ class Article extends Model<InferAttributes<Article>, InferCreationAttributes<Ar
as: 'articles',
},
foreignKey: 'targetId',
constraints: false,
foreignKeyConstraints: false,
scope: {
targetModel: 'article',
},
Expand Down
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