Creating Mappings with Hibernate XML Files - Beginning Hibernate: From Novice to Professional - page 149

Table 7-6. The <property> Attributes

Attribute Values Default Description

access

Defines how the properties should be accessed:
through field (directly), through property (calling
the get/set methods), or through the name of a
PropertyAccessor class to be used. The value from
the <class> element or <hibernate-mapping> element
will be inherited if this is not specified.

column

The column in which the property will be main-
tained. If omitted, this will default to the name of the
attribute; or it can be specified with nested <column>
elements (see Listing 7-2).

formula

An arbitrary SQL query representing a computed
property (i.e., one that is calculated dynamically,
rather than represented in a column).

index The name of an index to be maintained for the

column.

insert true , false true Specifies whether creation of an instance of the class

should result in the column associated with this
attribute being included in insert statements.

lazy true , false false

Defines whether lazy instantiation is used by default
for this column.

length

The column length to be used.

name The (mandatory) name of the attribute. This should

start with a lowercase letter.

node Specifies the name of the XML element or attribute

that should be used by the XML relational persist-
ence features.

not-null true , false false

Specifies whether the column is permitted to contain
null values.

optimistic-lock true , false true

Determines whether optimistic locking should be
used when the attribute has been updated.

precision

Allows the precision (the number of digits) to be
specified for numeric data.

scale

Allows the scale (the number of digits to the right of
the decimal point) to be specified for numeric data.

type

The Hibernate type of the column.

unique true , false false Indicates whether duplicate values are permitted for

this column/attribute.

unique-key Groups the columns together by this attribute value.

Represents columns across which a unique key con-
straint should be generated (not yet supported in the
schema generation).

update true , false true Specifies whether changes to this attribute in

instances of the class should result in the column
associated with this attribute being included in
update statements.