mirror of https://github.com/go-gorm/gorm.git
41 lines
1.5 KiB
Markdown
41 lines
1.5 KiB
Markdown
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# Association Mode
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Association Mode contains some helper methods to handle relationship things easily.
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```go
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// Start Association Mode
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var user User
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db.Model(&user).Association("Languages")
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// `user` is the source, it need to be a valid record (contains primary key)
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// `Languages` is source's field name for a relationship.
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// If those conditions not matched, will return an error, check it with:
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// db.Model(&user).Association("Languages").Error
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// Query - Find out all related associations
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db.Model(&user).Association("Languages").Find(&languages)
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// Append - Append new associations for many2many, has_many, will replace current association for has_one, belongs_to
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db.Model(&user).Association("Languages").Append([]Language{languageZH, languageEN})
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db.Model(&user).Association("Languages").Append(Language{Name: "DE"})
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// Delete - Remove relationship between source & passed arguments, won't delete those arguments
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db.Model(&user).Association("Languages").Delete([]Language{languageZH, languageEN})
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db.Model(&user).Association("Languages").Delete(languageZH, languageEN)
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// Replace - Replace current associations with new one
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db.Model(&user).Association("Languages").Replace([]Language{languageZH, languageEN})
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db.Model(&user).Association("Languages").Replace(Language{Name: "DE"}, languageEN)
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// Count - Return the count of current associations
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db.Model(&user).Association("Languages").Count()
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// Clear - Remove relationship between source & current associations, won't delete those associations
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db.Model(&user).Association("Languages").Clear()
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```
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