What is propagation in spring transaction?
Transaction Propagation Propagation defines our business logic's transaction boundary. Spring manages to start and pause a transaction according to our propagation setting. Spring calls TransactionManager::getTransaction to get or create a transaction according to the propagation.
What is required propagation?
The REQUIRED propagation can be interpreted as follows: If there is no existing physical transaction, then the Spring container will create one. If there is an existing physical transaction, then the methods annotated with REQUIRE will participate in this physical transaction.
What is spring nested propagation?
For NESTED propagation, Spring checks if a transaction exists, and if so, it marks a save point. This means that if our business logic execution throws an exception, then the transaction rollbacks to this save point.
What does propagation support do?
Propagation.SUPPORTS states that if a physical transaction exists, then it will execute the demarcated method as a logical transaction in the context of this physical transaction. Otherwise, it will execute this method outside of a physical transaction. Let’s see some code:
How many types of propagation are there in Spring?
There are two types of propagation: sexual and asexual.
What is propagation behavior?
Transaction propagation indicates what should be the behaviour of the given method when it is invoked. REQUIRES_NEW means that a new transaction should always be started, even if there is an ongoing transaction. If method1() , for example, defines REQUIRES_NEW , than it will execute in a new transaction.
When the propagation setting is?
When the propagation setting is PROPAGATION_REQUIRED, a logical transaction scope is created for each method upon which the setting is applied.
What is propagation Requires_new?
REQUIRES_NEW is that even if the inner method fails to execute (because of some exception), the outer method commits the transaction. That causes inconsistency in data. If you use Propagation. REQUIRED, then if both inner/outer methods execute without fail, then only the data will be persisted to the database.
What's meant by propagation?
: the act or action of propagating: such as. : increase (as of a kind of organism) in numbers. : the spreading of something (such as a belief) abroad or into new regions. : enlargement or extension (as of a crack) in a solid body.
What is meant propagation?
The act or process of propagating, especially the process by which a disturbance, such as the motion of electromagnetic or sound waves, is transmitted through a medium such as air or water.
What is @transactional in spring boot?
The @Transactional annotation is metadata that specifies that an interface, class, or method must have transactional semantics; for example, "start a brand new read-only transaction when this method is invoked, suspending any existing transaction".
What is propagation level in Spring transaction?
Propagation is the ability to decide how the business methods should be encapsulated in both logical or physical transactions. Spring REQUIRED behavior means that the same transaction will be used if there is an already opened transaction in the current bean method execution context.
What is @transactional used for?
The @Transactional annotation is the metadata that specifies the semantics of the transactions on a method. We have two ways to rollback a transaction: declarative and programmatic. In the declarative approach, we annotate the methods with the @Transactional annotation.
What is @transactional readOnly?
If we use @Transactional(readOnly = true) to a method which is performing create or update operation then we will not have newly created or updated record into the database but we will have the response data.
Is @transactional mandatory?
@Transactional(MANDATORY) : fails if no transaction was started ; works within the existing transaction otherwise. @Transactional(SUPPORTS) : if a transaction was started, joins it ; otherwise works with no transaction.
Is @transactional an aspect?
The Transactional Aspect is an 'around' aspect that gets called both before and after the annotated business method. The concrete class for implementing the aspect is TransactionInterceptor .
What is example of propagation?
Propagation is the reproduction or spreading of something. When a plant or animal reproduces, this is an example of propagation. When an idea or a trend spreads to a new area, this is an example of propagation.
What does propagation mean in physiology?
verb. (1) To cause an organism to reproduce or breed, especially by natural means. (2) To transmit or spread (e.g. hereditary characteristic) from one generation to another. (3) To disseminate or cause to move in some direction, as nerve impulse.
What does propagation mean in networking?
The transmission (spreading) of signals from one place to another.
What are the four types of propagation?
Plant propagation can be divided into four basic types: sexual, asexual (vegetative), layering, and grafting. Countless plants are propagated each day in horticulture and agriculture. The materials commonly used for plant propagation are seeds and cuttings.
What is propagation in Spring?
Propagation defines our business logic's transaction boundary. Spring manages to start and pause a transaction according to our propagation setting.
What is nonrepeatable read?
Nonrepeatable read: get different value on re-read of a row if a concurrent transaction updates the same row and commits
What happens if a transaction exists in Spring?
If a current transaction exists, first Spring suspends it , and then the business logic is executed without a transaction:
What is the third level of isolation?
The third level of isolation, REPEATABLE_READ, prevents dirty, and non-repeatable reads. So we are not affected by uncommitted changes in concurrent transactions.
What does Spring check for?
For SUPPORTS, Spring first checks if an active transaction exists. If a transaction exists, then the existing transaction will be used. If there isn't a transaction, it is executed non-transactional:
What are the properties of ACID?
Isolation is one of the common ACID properties: Atomicity, Consistency, Isolation, and Durability. Isolation describes how changes applied by concurrent transactions are visible to each other.
What is a proxy in Spring?
Spring creates a proxy, or manipulates the class byte-code, to manage the creation, commit, and rollback of the transaction. In the case of a proxy, Spring ignores @Transactional in internal method calls.
Introduction
While dealing with Spring managed transactions the developer is able to specify how the transactions should behave in terms of propagation. In other words the developer has the ability to decide how the business methods should be encapsulated in both logical or physical transactions.
REQUIRED behavior
Spring REQUIRED behavior means that the same transaction will be used if there is an already opened transaction in the current bean method execution context. If there is no existing transaction the Spring container will create a new one.
NESTED behavior
The NESTED behavior makes nested Spring transactions to use the same physical transaction but sets savepoints between nested invocations so inner transactions may also rollback independently of outer transactions.
MANDATORY behavior
The MANDATORY behavior states that an existing opened transaction must already exist. If not an exception will be thrown by the container.
NEVER behavior
The NEVER behavior states that an existing opened transaction must not already exist. If a transaction exists an exception will be thrown by the container.
SUPPORTS behavior
The SUPPORTS behavior will execute in the scope of a transaction if an opened transaction already exists. If there isn't an already opened transaction the method will execute anyway but in a non-transactional way.
Quick note about the full source code
The full source code available at the end of this page considers the following MySQL table:
