Gorm How to select additional custom fields when using Smart Select Fields?

Your Question

I'd like to select something when using Smart Select Fields for example, Location table is

type Location struct {
    gorm.Model
    Name     string `gorm:"not null"`
    X        int32  `gorm:"not null; index"`
    Y        int32  `gorm:"not null; index"`
    Address  string `gorm:"not null"`
}

And I'd like to select more columns such as Distance in example

type APILocation struct {
    Id      uint
    Name    string
    X       int32
    Y       int32
    Address string
    Distance int32 // Location table doesn't have this field
}

In this case,

db.
Select(fmt.Sprintf("(x - %v) * (x - %v) + (y - %v) * (y - %v) as Distance", X, X, Y, Y)).
Model(&model.Location{}).
Find(&model.APILocation{})

It select every fields in APILocation plus distance. But if I use parameterized queries, like

db.
Select("(x - ?) * (x - ?) + (y - ?) * (y - ?) as Distance", home.X, home.X, home.Y, home.Y).
Model(&model.Location{}).
Find(&model.APILocation{})

Select overwrites Smart Select Fields and it selects only distance

How can I select additional custom fields with smart select fields?

The document you expected this should be explained

It explains only how to use smart select fields.

Expected answer

How to select additional fields

Comment From: a631807682

db.
- Select("(x - ?) * (x - ?) + (y - ?) * (y - ?) as Distance", home.X, home.X, home.Y, home.Y).
+ Select("*,(x - ?) * (x - ?) + (y - ?) * (y - ?) as Distance", home.X, home.X, home.Y, home.Y).
Model(&model.Location{}).
Find(&model.APILocation{})

I didn't quite understand your question, if you want to include other fields

Comment From: SuhwanCha

@a631807682 Sorry for the confusing question. If I use the smart select field, only fields in the struct will be selected automatically. My question is how to select additional fields with smart select fields, which means not to select every field but smart select fields plus something, not using asterisk

Comment From: a631807682

You can use scope, first you need to parse the schema, and then automatically add schema.DBNames to the original select.

https://gorm.io/docs/scopes.html#content-inner

tx.Statement.Schema.Parse
...
for sch range tx.Statement.Schema.DBNames {
...
}
...
tx.Statement.Selects = ...