Gorm Gorm how to set field allowing to be null in model definition?

In model definition, I set a field not allowed to be null before.

type Dataset struct {
    MD5         string                  `gorm:"type:string;size:32;not null"`
}

But now I want to set field allowing to be null in the model definition.

I do as follow but it doesn't work.

type Dataset struct {
    MD5         string                  `gorm:"type:string;size:32;null"`
}

// or
type Dataset struct {
    MD5         string                  `gorm:"type:string;size:32"`
}

So how to remove the not null property? thx.

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Comment From: github-actions[bot]

Comment From: yousifnimah

You can use sql.NullString as a field type. it accepts nil or string

1- Import "database/sql" 2- Change the type to sql.NullString

Example:

 type Dataset struct {
    MD5    sql.NullString   `gorm:"type:string;size:32;null"`
}

and for NullInteger :

  type Dataset struct {
    MD5    sql.NullInt32   `gorm:"type:string;size:32;null"`
}

Comment From: github-actions[bot]