Struct ForeignKey 

pub struct ForeignKey {
    pub table: Cow<'static, str>,
    pub name: Cow<'static, str>,
    pub columns: Cow<'static, [Cow<'static, str>]>,
    pub table_to: Cow<'static, str>,
    pub columns_to: Cow<'static, [Cow<'static, str>]>,
    pub on_delete: Option<Cow<'static, str>>,
    pub on_update: Option<Cow<'static, str>>,
    pub name_explicit: bool,
}

A foreign key, as stored in migration snapshots.

Actions are stored as SQL keywords ("CASCADE", …); None means not written.

Fields

table: Cow<'static, str>

Parent table name

name: Cow<'static, str>

Constraint name

columns: Cow<'static, [Cow<'static, str>]>

Source columns

table_to: Cow<'static, str>

Referenced table name

columns_to: Cow<'static, [Cow<'static, str>]>

Referenced columns

on_delete: Option<Cow<'static, str>>

ON DELETE action (as SQL string)

on_update: Option<Cow<'static, str>>

ON UPDATE action (as SQL string)

name_explicit: bool

Whether the user gave the constraint name (rather than it being generated)

Implementations

impl ForeignKey

pub fn new( table: impl Into<Cow<'static, str>>, name: impl Into<Cow<'static, str>>, columns: impl Into<Cow<'static, [Cow<'static, str>]>>, table_to: impl Into<Cow<'static, str>>, columns_to: impl Into<Cow<'static, [Cow<'static, str>]>>, ) -> Self

Creates a foreign key with no actions.

pub fn from_strings( table: String, name: String, columns: Vec<String>, table_to: String, columns_to: Vec<String>, ) -> Self

Creates a foreign key with no actions from owned strings.

pub fn on_delete(self, action: impl Into<Cow<'static, str>>) -> Self

Sets the ON DELETE action, as SQL keywords.

pub fn on_update(self, action: impl Into<Cow<'static, str>>) -> Self

Sets the ON UPDATE action, as SQL keywords.

pub fn name(&self) -> &str

Returns the constraint name.

pub fn table(&self) -> &str

Returns the table name.

impl ForeignKey

pub fn to_constraint_sql(&self) -> String

Renders CONSTRAINT name FOREIGN KEY (...) REFERENCES table(...), with ON UPDATE / ON DELETE unless they are NO ACTION.

pub fn add_fk_sql(&self) -> String

Returns a SQL comment: SQLite cannot add a foreign key to an existing table without recreating it.

pub fn drop_fk_sql(&self) -> String

Returns a SQL comment: SQLite cannot drop a foreign key without recreating the table.

Trait Implementations

impl Clone for ForeignKey

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 ForeignKey

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

Formats the value using the given formatter.

impl Default for ForeignKey

fn default() -> Self

Returns the “default value” for a type.

impl Eq for ForeignKey

impl From<ForeignKeyDef> for ForeignKey

fn from(def: ForeignKeyDef) -> Self

Converts to this type from the input type.

impl PartialEq for ForeignKey

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for ForeignKey