Getting Startedwith pureQuery

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Getting Started with pureQuery
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• @ColumnOverride
o
provides a single column to property mapping at the bean field level, and is
applied to either the public getter method or the public setter method or the
public field
provides a single override for a column-to-property mapping at the bean
class level that will override a mapping defined using @Column. It will
override the default mapping or any column mapping specified elsewhere
for the bean, even in one of the bean’s superclasses.
• @ColumnOverrides
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• @GeneratedKey
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provides a list of column-to-property mappings at the bean class level that
override mappings set using @Column. It will override either the default
mapping, or any mappings specified elsewhere for the bean, even in one
of the bean’s superclasses. @ColumnOverrides makes it easy to define a
bean subclass which needs to map to and from the relational layer
differently than its superclass. This annotation is not used with
@ColumnOverride. They are mutually exclusive.
indicates a property which will be populated by a database generated
value, and is applied to either the public getter method or the public setter
method or the public field. The indicated property is populated prior to
returning from an annotated method in which the bean is used as a
parameter for an SQL insert statement that returns a generated key value.
(The annotation is only supported when the bean is used for non-batched
inserts).
When using annotations to override pureQuery’s default mapping mechanism, it is a best
programming practice to be consistent when choosing which bean members to apply the
annotations to, such as always applying @Column annotations to the public getter
methods (this prevents the mistake of accidentally applying two mapping annotations for
the same field, for example, one on the getter and one on the setter).
If you use a pureQuery bean to set the SQL parameters of a DML statement, you must use
parameter markers to indicate the name of the bean properties that correspond to the SQL
parameters.
Table 3.1 shows some simple examples using the default pureQuery data access layer
mapping between bean fields and SQL results or parameters. For a complete description
of all the options for bean mapping, see the online pureQuery documentation:
sql property of
annotated
method
SELECT EMPNO
FROM EMPLOYEE
pureQuery
bean
Annotation
Bean field or
method
pureQuery mapping rule
none setEmpno() Result column name is a case
insensitive match to a field with a
public accessor method