Identify correct and incorrect statements or examples about the purpose and use of EJB QL.

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Identify correct and incorrect statements or examples about the purpose and use of EJB QL.

Identify correct and incorrect statements or examples about the purpose and use of EJB QL.
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Identify correct and incorrect statements or examples about the purpose and use of EJB QL.

Find all orders: 
SELECT OBJECT(o)
FROM Order o
Find all orders that need to be shipped to Colorado: 
SELECT OBJECT(o)
FROM Order o
WHERE o.shipping_address.state = 'CO'
Find all states for which there are orders: 
SELECT DISTINCT o.shipping_address.state
FROM Order o
Find all orders that have line items: 
SELECT DISTINCT OBJECT(o)
FROM Order o, IN(o.lineItems) l
This query can also be written as: 
SELECT OBJECT(o)
FROM Order o
WHERE o.lineItems IS NOT EMPTY
Find all orders that have no line items: 
SELECT OBJECT(o)
FROM Order o
WHERE o.lineItems IS EMPTY
Find all pending orders: 
SELECT DISTINCT OBJECT(o)
FROM Order o, IN(o.lineItems) l
WHERE l.shipped = FALSE
Find all orders in which the shipping address differs from the billing address. This example assumes that the Bean Provider uses two distinct entity beans to designate shipping and billing addresses: 
SELECT OBJECT(o)
FROM Order o
WHERE NOT 
	(o.shipping_address.state = o.billing_address.state AND
	o.shipping_address.city = o.billing_address.city AND
	o.shipping_address.street = o.billing_address.street)
If the Bean Provider uses a single entity bean in two different relationships for both the shipping address and the billing address, the above expression can be rewritten as: 

SELECT OBJECT(o)
FROM Order o
WHERE o.shipping_address <> o.billing_address
Find all orders for a book titled 'Head First EJB': 
SELECT DISTINCT OBJECT(o)
FROM Order o, IN(o.lineItems) l
WHERE l.product.type = 'book' AND
	l.product.name = 'Head First EJB'
The following query finds the orders for a product whose name is designated by an input parameter (the input parameter must be of the type of the product name, i.e., a String): 
SELECT DISTINCT OBJECT(o)
FROM Order o, IN(o.lineItems) l
WHERE l.product.name = ?1
The following EJB QL query selects the names of all products that have been ordered. It illustrates the selection of values other than entity beans, therefore it can be used only for SELECT methods, not for FINDER methods: 
SELECT DISTINCT l.product.name
FROM Order o, IN(o.lineItems) l
The following query finds the names of all products in the order specified by a particular order number. 
SELECT l.product.name
FROM Order o, IN(o.lineItems) l
WHERE o.ordernumber = ?1
The following query returns the names of all the cities of the shipping addresses of all orders. The result type of the SELECT method, which is either java.util.Collection or java.util.Set, determines whether the query may return duplicate city names. 
SELECT o.shipping_address.city
FROM Order o

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Chapter 9. EJB-QL Home Identify correct and incorrect conditional expressions, BETWEEN expressions, IN expressions, LIKE expressions, and comparison expressions.

Tutorials

  1. Appendix A. First Appendix
  2. Second Section
  3. Third Section
  4. Part II. Appendixes
  5. From a list, identify the responsibility of the bean provider and the responsibility of the container provider for a message-driven bean.
  6. Chapter 6. Component Contract for Container-Managed Persistence (CMP)
  7. Identify correct and incorrect statements or examples about persistent relationships, remove protocols, and about the abstract schema type of a CMP entity bean.
  8. Identify the interfaces and methods a CMP entity bean must and must not implement.
  9. Match the name with a description of purpose or functionality, for each of the following deployment descriptor elements: ejb-name, abstract-schema-name, ejb-relation, ejb-relat
  10. Identify correctly-implemented deployment descriptor elements for a CMP bean (including container-managed relationships).
  11. From a list, identify the purpose, behavior, and responsibilities of the bean provider for a CMP entity bean, including but not limited to: setEntityContext, unsetEntityContext, ejbC
  12. Chapter 7. CMP Entity Bean Life Cycle
  13. Identify correct and incorrect statements or examples about the rules and semantics for relationship assignment and relationship updating in a CMP bean.
  14. From a list, identify the responsibility of the container for a CMP entity bean, including but not limited to: setEntityContext, unsetEntityContext, ejbCreate, ejbPostCreate, ejbActi
  15. Given a code listing, determine whether it is a legal and appropriate way to programmatically access a caller's security context.
  16. Chapter 10. Message-Driven Bean Component Contract
  17. Identify correct and incorrect statements about the purpose and use of the deployment descriptor elements for environment entries, EJB references, and resource manager connection factory r
  18. Identify the use and the behavior of the ejbPassivate method in a session bean, including the responsibilities of both the container and the bean provider.
  19. Chapter 12. Exceptions
  20. Identify correct and incorrect statements or examples about the client view of an entity bean's local component interface (EJBLocalObject).
  21. Identify EJB 2.0 container requirements.
  22. Chapter 1. EJB Overview
  23. Identify correct and incorrect statements or examples about EJB programming restrictions.
  24. Chapter 9. EJB-QL
  25. Identify correct and incorrect statements or examples about the purpose and use of EJB QL.
  26. Identify correct and incorrect conditional expressions, BETWEEN expressions, IN expressions, LIKE expressions, and comparison expressions.
  27. Identify correct and incorrect statements or examples about the client view of a entity bean's remote component interface (EJBObject).
  28. Given a list, identify which are requirements for an EJB-jar file.
  29. Match EJB roles with the corresponding description of the role's responsibilities, where the description may include deployment descriptor information.
  30. Chapter 2. Client View of a Session Bean
  31. Chapter 13. Enterprise Bean Environment
  32. Chapter 8. Entity Beans
  33. Identify the use, syntax, and behavior of, the following entity bean home method types, for Container-Managed Persistence (CMP); finder methods, create methods, remove methods, and home me
  34. Identify correct and incorrect statements or examples about an entity bean's primary key and object identity.
  35. Identify correct and incorrect statements or examples about the client's view of exceptions received from an enterprise bean invocation.
  36. Identify correct and incorrect statements or examples about application exceptions and system exceptions in entity beans, session beans, and message-driven beans.
  37. Given a particular method condition, identify the following: whether an exception will be thrown, the type of exception thrown, the container's action, and the client's view.
  38. Given a list of responsibilities related to exceptions, identify those which are the bean provider's, and those which are the responsibility of the container provider. Be prepared to recog
  39. SCBCD Study Guide
  40. Identify the use and behavior of the MessageDrivenContext interface methods.