Struct ColumnChanges 

pub struct ColumnChanges {
    pub nullable: Option<bool>,
    pub unique: Option<bool>,
    pub auto_increment: Option<bool>,
    pub primary_key: Option<bool>,
    pub foreign_key: Option<Option<ForeignKeySnapshot>>,
}

Bundle of constraint-flag deltas for an MigrationOp::AlterColumn.

Each field is Some(new_value) only when that flag changed between the stored and compiled snapshots; otherwise it stays None.

Fields

nullable: Option<bool>

New value for the nullable flag, if changed.

unique: Option<bool>

New value for the unique flag, if changed.

auto_increment: Option<bool>

New value for the auto_increment flag, if changed.

primary_key: Option<bool>

New value for the primary_key flag, if changed.

foreign_key: Option<Option<ForeignKeySnapshot>>

New foreign-key state. Some(None) means the foreign key was dropped; Some(Some(fk)) means it was added or replaced.

The serde representation is meant for self-describing, human-readable formats such as JSON: None omits the field, Some(None) is written as null, and Some(Some(fk)) as the snapshot. It must not be used with non-self-describing binary serde formats, because the omitted field shifts the positions of the following ones. Candid has its own encoding.

Implementations

impl ColumnChanges

pub fn is_empty(&self) -> bool

Returns true if no flag actually changed.

Trait Implementations

impl Clone for ColumnChanges

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ColumnChanges

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for ColumnChanges

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for ColumnChanges

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for ColumnChanges

impl PartialEq for ColumnChanges

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl Serialize for ColumnChanges

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for ColumnChanges