Gorm: Postgresql Arrays

[ghost]

Hello, what about postgresql arrays? As I understand if the type of field is slice - gorm interprets it like associations. And if it's []string for example there is go panic: "reflect.Value.FieldByName on string Value"

I know MySQL don't have an array type (and this is very strange I think), but Postgresql uses it heavily.

[ghost]

I think I found a solution.

var Test struct {
   Scopes string
   ScopesArray []string `json:"-" sql:"-"`
}

func (m *Test) ToPGArray() {
  ... // logic to convert slice to string like "{hello, world}". Simple strings.Split will do.
}

func (m *Test) FromPGArray() {
  ... // logic to convert string to array. Simple strings.Split will do.
}

func (m *Test) BeforeSave() (err error) {
   m.ToPGArray()
   ...
}

func (m *Test) AfterFind() (err error) {
   m.FromPGArray()

}

Then all you have to do is:

dbConn.Save(Test{ScopesArray: []string{"hello", "world"}})

[ghost]

Method above doesn't work because any slice interprets like association I guess. Even tag: sql:"-" doesn't work, so no internal custom array fields :)

[jinzhu]

HI @reterius

You could use the new plugin system to do this. https://github.com/jinzhu/gorm/blob/master/doc/development.md

With it, you could rewrite some callbacks and do everything. I would like to write an example but kind of too busy to do this now ;(

If you want to give it a try, let me know if you need any help, thank you.

[jinzhu]

The panic thing should be fixed. I think maybe better, you should write a Scanner to handle those things.

[wenweih]

"github.com/lib/pq" can add array datatype feature to gorm

something like that:

import (
  ...
  "github.com/lib/pq"
  ...
)

...
type Block struct {
    gorm.Model
        .....
    Tx                pq.StringArray `gorm:"type:varchar(100)[]"`
}

[challarao]

Is there a similar thing for UUID array?