Struct SchemaDiff 

pub struct SchemaDiff {
    pub added_tables: Vec<String>,
    pub dropped_tables: Vec<String>,
    pub added_columns: Vec<(String, String)>,
    pub dropped_columns: Vec<(String, String)>,
    pub type_changes: Vec<(String, String, String, String)>,
    pub nullability_changes: Vec<(String, String, bool)>,
}

Description of the changes a deploy is about to apply, passed as the payload to the on_migrate hook so user code can decide which backfill blocks should fire.

Fields

added_tables: Vec<String>

dropped_tables: Vec<String>

added_columns: Vec<(String, String)>

(table, column) pairs for newly added columns. In phase 2 these already exist in the database (added in phase 1) but may be NULL on existing rows; the hook is the place to backfill them.

dropped_columns: Vec<(String, String)>

(table, column) pairs for columns that will be dropped in phase 3. During phase 2 these are still present in the database, so the hook can read them to populate new columns before they disappear.

type_changes: Vec<(String, String, String, String)>

(table, column, old_type, new_type)

nullability_changes: Vec<(String, String, bool)>

(table, column, new_nullable)

Implementations

impl SchemaDiff

pub fn added_column(&self, table: &str, col: &str) -> bool

pub fn dropped_column(&self, table: &str, col: &str) -> bool

pub fn added_table(&self, table: &str) -> bool

pub fn dropped_table(&self, table: &str) -> bool

pub fn is_empty(&self) -> bool

Trait Implementations

impl Clone for SchemaDiff

fn clone(&self) -> SchemaDiff

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for SchemaDiff

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

Formats the value using the given formatter.

impl Default for SchemaDiff

fn default() -> SchemaDiff

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for SchemaDiff

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for SchemaDiff

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

where __S: Serializer,

Serialize this value into the given Serde serializer.