Identify correct and incorrect conditional expressions, BETWEEN expressions, IN expressions, LIKE expressions, and comparison expressions.

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Identify correct and incorrect conditional expressions, BETWEEN expressions, IN expressions, LIKE expressions, and comparison expressions.

Identify correct and incorrect conditional expressions, BETWEEN expressions, IN expressions, LIKE expressions, and comparison expressions.
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Identify correct and incorrect conditional expressions, BETWEEN expressions, IN expressions, LIKE expressions, and comparison expressions.

Conditional expressions

Conditional expressions are composed of other conditional expressions, comparison operations, logical operations, path expressions that evaluate to boolean values, and boolean literals.

Arithmetic expressions can be used in comparison expressions. Arithmetic expressions are composed of other arithmetic expressions, arithmetic operations, path expressions that evaluate to numeric values, and numeric literals.

Arithmetic operations use Java numeric promotion.

Standard bracketing () for ordering expression evaluation is supported.

BETWEEN expressions

The syntax for the use of the comparison operator [NOT] BETWEEN in an conditional expression is as follows:

arithmetic_expression [NOT] BETWEEN arithmetic-expr AND arithmetic-expr 


p.age BETWEEN 15 AND 19
is equivalent to 

p.age >= 15 AND p.age <= 19

					


p.age NOT BETWEEN 15 AND 19
is equivalent to 

p.age < 15 OR p.age > 19

IN expressions

The syntax for the use of the comparison operator [NOT] IN in a conditional expression is as follows:

single_valued_path_expression [NOT] IN (string-literal [, string-literal]* )

The single_valued_path_expression must have a String value. 

o.country IN ('UK', 'US', 'BY')
is equivalent to 
(o.country = 'UK') OR (o.country = 'US') OR (o.country = 'BY')
					

o.country NOT IN ('UK', 'US', 'BY')
is equivalent to 
NOT ((o.country = 'UK') OR (o.country = 'US') OR (o.country = 'BY'))

LIKE expressions

The syntax for the use of the comparison operator [NOT] LIKE in a conditional expression is as follows:

single_valued_path_expression [NOT] LIKE pattern-value [ESCAPE escape-character]

The single_valued_path_expression must have a String value. The pattern-value is a string literal in which an underscore (_) stands for ANY SINGLE character, a percent (%) character stands for ANY SEQUENCE of characters (including the empty sequence), and all other characters stand for themselves. The optional escape-character is a single character string literal and is used to escape the special meaning of the underscore and percent characters in pattern-value. 

address.phone LIKE '12%3'
TRUE for '123' '12993', FALSE for '1234'.

asentence.word LIKE 'l_se'
TRUE for 'lose', FALSE for 'loose'.

aword.underscored LIKE '\_%' ESCAPE '\'
TRUE for '_foo', FALSE for 'bar'.

address.phone NOT LIKE '12%3'
TRUE for '1234', FALSE for '123' and '12993'.

NOTE, input parameters CANNOT be used in LIKE expression.

NULL comparison expressions

The syntax for the use of the comparison operator IS NULL in a conditional expression is as follows:

single_valued_path_expression IS [NOT ] NULL

A null comparison expression tests whether or not the single valued path expression is a NULL value. Path expressions containing NULL values during evaluation return NULL values.

EMPTY collection comparison expressions

The syntax for the use of the comparison operator IS EMPTY in an empty_collection_comparison_expression is as follows:

collection_valued_path_expression IS [NOT] EMPTY

This expression tests whether or not the collection designated by the collection-valued path expression is empty (i.e, has no elements). The collection designated by the collection-valued path expression used in an empty collection comparison expression MUST NOT be used in the FROM clause for the declaration of an identification variable. An identification variable declared as a member of a collection IMPLICITLY designates the existence of a non-empty relationship; testing whether the same collection is empty is CONTRADICTORY.

Collection member expressions

The syntax for the use of the comparison operator MEMBER OF in an collection_member_expression is as follows:

{single_valued_navigation | identification_variable | input_parameter } [NOT] MEMBER [OF] collection_valued_path_expression

This expression tests whether the designated value is a member of the collection specified by the collection-valued path expression.

String Functions:

  • CONCAT(String, String) returns a String 0

  • SUBSTRING(String, start, length) returns a String

  • LOCATE(String, String [, start]) returns an int

  • LENGTH(String) returns an int 1

Arithmetic Functions:

  • ABS(number) returns a number (int, float, or double)

  • SQRT(double) returns a double

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Identify correct and incorrect statements or examples about the purpose and use of EJB QL.  Home Chapter 10. Message-Driven Bean Component Contract

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.