Struct M0004 

pub struct M0004;

Migration that swaps idx_event_type for a composite cursor-scan index.

Changes

• Creates idx_event_type_routing_cursor on (aggregator_type, routing_key, timestamp, timestamp_subsec, version).
• Drops idx_event_type (redundant once the composite index exists — same leading column, planner will use the new one).

Notes

• name is intentionally not part of the index: it is only ever a per-aggregator-branch residual predicate inside an OR, and with the typical small set of event names per aggregator type the residual scan stays cheap.
• The ORDER BY tail stops at version; (timestamp, timestamp_subsec, version) is unique in practice, so the trailing id adds storage without eliminating any sort work.

Dependencies

This migration depends on M0003.

Trait Implementations

impl Migration<MySql> for M0004

fn app(&self) -> &str

Returns the application name associated with the migration. This can be the name of the folder or library where the migration is located.

fn name(&self) -> &str

Returns the migration name, typically the file name without the extension.

fn parents(&self) -> Vec<Box<dyn Migration<MySql>>>

Returns the list of parent migrations.

fn operations(&self) -> Vec<Box<dyn Operation<MySql>>>

Returns the operations associated with this migration.

fn replaces(&self) -> Vec<Box<dyn Migration<DB>>>

Returns the list of migrations that this migration replaces.

fn run_before(&self) -> Vec<Box<dyn Migration<DB>>>

Returns the list of migrations that this migration must run before(when applying) or after (when reverting).

fn is_atomic(&self) -> bool

Indicates whether the migration is atomic. By default, this function returns true, meaning the migration is atomic.

fn is_virtual(&self) -> bool

Indicates whether the migration is virtual. By default, this function returns false, meaning the migration is not virtual.

impl Migration<Postgres> for M0004

fn app(&self) -> &str

Returns the application name associated with the migration. This can be the name of the folder or library where the migration is located.

fn name(&self) -> &str

Returns the migration name, typically the file name without the extension.

fn parents(&self) -> Vec<Box<dyn Migration<Postgres>>>

Returns the list of parent migrations.

fn operations(&self) -> Vec<Box<dyn Operation<Postgres>>>

Returns the operations associated with this migration.

fn replaces(&self) -> Vec<Box<dyn Migration<DB>>>

Returns the list of migrations that this migration replaces.

fn run_before(&self) -> Vec<Box<dyn Migration<DB>>>

Returns the list of migrations that this migration must run before(when applying) or after (when reverting).

fn is_atomic(&self) -> bool

Indicates whether the migration is atomic. By default, this function returns true, meaning the migration is atomic.

fn is_virtual(&self) -> bool

Indicates whether the migration is virtual. By default, this function returns false, meaning the migration is not virtual.

impl Migration<Sqlite> for M0004

fn app(&self) -> &str

Returns the application name associated with the migration. This can be the name of the folder or library where the migration is located.

fn name(&self) -> &str

Returns the migration name, typically the file name without the extension.

fn parents(&self) -> Vec<Box<dyn Migration<Sqlite>>>

Returns the list of parent migrations.

fn operations(&self) -> Vec<Box<dyn Operation<Sqlite>>>

Returns the operations associated with this migration.

fn replaces(&self) -> Vec<Box<dyn Migration<DB>>>

Returns the list of migrations that this migration replaces.

fn run_before(&self) -> Vec<Box<dyn Migration<DB>>>

Returns the list of migrations that this migration must run before(when applying) or after (when reverting).

fn is_atomic(&self) -> bool

Indicates whether the migration is atomic. By default, this function returns true, meaning the migration is atomic.

fn is_virtual(&self) -> bool

Indicates whether the migration is virtual. By default, this function returns false, meaning the migration is not virtual.