Struct RenameHints 

pub struct RenameHints { /* private fields */ }

Hints that tell the diff algorithm which schema items were renamed.

Without rename hints, a renamed table/column/index appears as a drop followed by a create. Adding a hint maps the old ID to the new ID so the diff produces an alter instead.

Examples

use toasty_core::schema::db::{RenameHints, TableId};

let mut hints = RenameHints::new();
hints.add_table_hint(TableId(0), TableId(1));
assert_eq!(hints.get_table(TableId(0)), Some(TableId(1)));
assert_eq!(hints.get_table(TableId(2)), None);

Implementations

impl RenameHints

pub fn new() -> Self

Creates an empty set of rename hints.

pub fn add_table_hint(&mut self, from: TableId, to: TableId)

Records that the table previously identified by from is now identified by to.

pub fn add_column_hint(&mut self, from: ColumnId, to: ColumnId)

Records that the column previously identified by from is now identified by to.

pub fn add_index_hint(&mut self, from: IndexId, to: IndexId)

Records that the index previously identified by from is now identified by to.

pub fn get_table(&self, from: TableId) -> Option<TableId>

Returns the new TableId if a rename hint exists for from.

pub fn get_column(&self, from: ColumnId) -> Option<ColumnId>

Returns the new ColumnId if a rename hint exists for from.

pub fn get_index(&self, from: IndexId) -> Option<IndexId>

Returns the new IndexId if a rename hint exists for from.

Trait Implementations

impl Default for RenameHints

fn default() -> RenameHints

Returns the “default value” for a type.