GORM Set size for the string field

In GORM package, you can specify field’s size using 2 options.

1. Using gorm:size tag
2. Using gorm:type tag

An example using gorm:size:

type Article struct {
	gorm.Model

	Source   Source `json:"source" gorm:"foreignkey:SourceID"`
	SourceID uint   `json:"sourde_ref"`
	Group    string `json:"group" gorm:"not null"`
	FromURL  string `json:"from_url"`
	URL      string `json:"url" gorm:"unique;not null"`

	Title           string `json:"title" gorm:"size:1000"`
	Description     string `json:"description" gorm:"size:65535"`
	Content         string `json:"content" gorm:"size:65535"`
	AuthorName      string
	AuthorEmail     string
	ImageURL        string
	ImageTitle      string
	Published       string
	PublishedParsed *time.Time
	Updated         string
	UpdatedParsed   *time.Time
	Categories      string
}

Another example using gorm:type:

type User struct {
  gorm.Model
  Name         string
  Age          sql.NullInt64
  Birthday     *time.Time
  Email        string  `gorm:"type:varchar(100);unique_index"`
}

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