Struct TransactionModes 

pub struct TransactionModes {
    pub isolation: Option<IsolationLevel>,
    pub read_only: Option<bool>,
    pub deferrable: Option<bool>,
}

v7.39 (round 293, E3 Phase 1) — a row-locking clause.

spg-sql cannot depend on spg-engine, so the strengths and policies are spelled again here and mapped at the engine boundary. v7.39 — the modes BEGIN / START TRANSACTION / SET TRANSACTION / SET SESSION CHARACTERISTICS accept. read_only used to be parsed and dropped on the floor, so BEGIN READ ONLY opened an ordinary read-write transaction and every write in it was accepted.

None on either field means the statement did not name that mode, so the session default applies — which is not the same as naming the default explicitly.

Fields

isolation: Option<IsolationLevel>

read_only: Option<bool>

Some(true) = READ ONLY, Some(false) = READ WRITE.

deferrable: Option<bool>

v7.40.12 — Some(true) = DEFERRABLE, Some(false) = NOT DEFERRABLE. PG reports it through transaction_deferrable, and consults it only for a SERIALIZABLE READ ONLY transaction, where it may make the transaction WAIT for a snapshot it can run against without serialization failures. SPG reports the property and does not defer; the difference a client can observe is a wait, never a different answer.

Trait Implementations

impl Clone for TransactionModes

fn clone(&self) -> TransactionModes

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for TransactionModes

impl Debug for TransactionModes

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

Formats the value using the given formatter.

impl Default for TransactionModes

fn default() -> TransactionModes

Returns the “default value” for a type.

impl Eq for TransactionModes

impl PartialEq for TransactionModes

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for TransactionModes