Reference documentation and code samples for the Cloud Spanner V1 API module Google::Cloud::Spanner::V1::TransactionOptions::ReadWrite::ReadLockMode.
ReadLockMode is used to set the read lock mode for read-write
transactions.
Constants
READ_LOCK_MODE_UNSPECIFIED
value: 0 Default value.
If the value is not specified, the pessimistic read lock is used.
PESSIMISTIC
value: 1 Pessimistic lock mode.
Read locks are acquired immediately on read.
OPTIMISTIC
value: 2 Optimistic lock mode.
Locks for reads within the transaction are not acquired on read.
Instead the locks are acquired on a commit to validate that
read/queried data has not changed since the transaction started.
