db/schema/column_definition.go

package schema

type ColumnDefinition struct {
	Type string // kind of column, string / int
	Name string // name of column
	ColumnOptions
}

type ColumnOptions struct {
	Length        int      // 字段长度
	Allowed       []string // enum 选项
	Precision     int      // 日期时间精度
	Total         int      // 小数位数
	Places        int      // 小数精度
	rename        string   // 重命名
	useCurrent    bool     // CURRENT TIMESTAMP
	after         string   // Place the column "after" another column (MySQL)
	always        bool     // Used as a modifier for generatedAs() (PostgreSQL)
	autoIncrement bool     // Set INTEGER columns as auto-increment (primary key)
	change        bool     // Change the column
	charset       string   // Specify a character set for the column (MySQL)
	collation     string   // Specify a collation for the column (MySQL/PostgreSQL/SQL Server)
	comment       string   // Add a comment to the column (MySQL)
	def           any      // Specify a "default" value for the column
	first         bool     // Place the column "first" in the table (MySQL)
	nullable      bool     // Allow NULL values to be inserted into the column
	storedAs      string   // Create a stored generated column (MySQL)
	unsigned      bool     // Set the INTEGER column as UNSIGNED (MySQL)
	virtualAs     string   // Create a virtual generated column (MySQL)
	unique        bool     // Add a unique index
	primary       bool     // Add a primary index
	index         bool     // Add an index
	spatialIndex  bool     // Add a spatial index
}

// VirtualAs Create a virtual generated column (MySQL)
func (c *ColumnDefinition) VirtualAs(as string) *ColumnDefinition {
	c.virtualAs = as
	return c
}

// StoredAs Create a stored generated column (MySQL)
func (c *ColumnDefinition) StoredAs(as string) *ColumnDefinition {
	c.storedAs = as
	return c
}

// Unsigned Set INTEGER columns as UNSIGNED (MySQL)
func (c *ColumnDefinition) Unsigned() *ColumnDefinition {
	c.unsigned = true
	return c
}

// First Place the column "first" in the table (MySQL)
func (c *ColumnDefinition) First() *ColumnDefinition {
	c.first = true
	return c
}

// Default Specify a "default" value for the column
func (c *ColumnDefinition) Default(def any) *ColumnDefinition {
	c.def = def
	return c
}

// Comment Add a comment to a column (MySQL/PostgreSQL)
func (c *ColumnDefinition) Comment(comm string) *ColumnDefinition {
	c.comment = comm
	return c
}

// Collaction Specify a collation for the column (MySQL/PostgreSQL/SQL Server)
func (c *ColumnDefinition) Collaction(coll string) *ColumnDefinition {
	c.collation = coll
	return c
}

// Charset Specify a character set for the column (MySQL)
func (c *ColumnDefinition) Charset(chars string) *ColumnDefinition {
	c.charset = chars
	return c
}

// AutoIncrement set INTEGER columns as auto-increment (primary key)
func (c *ColumnDefinition) AutoIncrement() *ColumnDefinition {
	c.autoIncrement = true
	return c
}

// After place the column "after" another column (MySQL)
func (c *ColumnDefinition) After(column string) *ColumnDefinition {
	c.after = column
	return c
}

// Nullable makes a column nullable
func (c *ColumnDefinition) Nullable() *ColumnDefinition {
	c.nullable = true
	return c
}

// 修改字段, 默认新增
func (c *ColumnDefinition) Change(param ...string) *ColumnDefinition {
	if len(param) > 0 && param[0] != "" {
		c.rename = param[0]
	}
	c.change = true
	return c
}

// 时间戳
func (c *ColumnDefinition) UseCurrent() *ColumnDefinition {
	c.useCurrent = true
	return c
}