Generation Options
Deployment descriptor elements or asadmin command
line options can control automatic schema generation by:
-
Creating tables during deployment
-
Dropping tables during undeployment
-
Dropping and creating tables during redeployment
-
Specifying the database vendor
-
Specifying that table names are unique
-
Specifying type mappings for individual CMP fields
Note –
Before using these options, make sure you have a properly configured
CMP resource. See Configuring the CMP Resource.
You can also use the deploytool to perform automatic mapping.
For more information about using the deploytool, see the “Create Database
Mapping” topic in the deploytool’s online help.
For
a read-only bean, do not create the database schema during deployment. Instead,
work with your database administrator to populate the data into the tables.
See Using Read-Only Beans.
Automatic
schema generation is not supported for beans with version column consistency
checking. Instead, work with your database administrator to create the schema
and add the required triggers. See Version Column Consistency Checking.
The following optional data subelements of the cmp-resource element in the sun-ejb-jar.xml file control
the automatic creation of database tables at deployment. For more information
about the cmp-resource element, see cmp-resource and Configuring the CMP Resource.
Table 7–3
sun-ejb-jar.xml Generation Elements
|
Element
|
Default
|
Description
|
|
create-tables-at-deploy
|
false
|
If true, causes database tables to be created for
beans that are automatically mapped by the EJB container. If false, does not create tables.
|
|
drop-tables-at-undeploy
|
false
|
If true, causes database tables that were automatically
created when the bean(s) were last deployed to be dropped when the bean(s)
are undeployed. If false, does not drop tables.
|
|
database-vendor-name
|
none
|
Specifies the name of the database vendor for which tables are created.
Allowed values are db2, mssql, oracle, derby, and sybase,
case-insensitive.
If no value is specified, a connection is made to the resource specified
by the jndi-name subelement of the cmp-resource element in the sun-ejb-jar.xml file, and the
database vendor name is read. If the connection cannot be established, or
if the value is not recognized, SQL-92 compliance is presumed.
|
|
schema-generator-properties
|
none
|
Specifies field-specific column attributes in property subelements.
Each property name is of the following format:
bean-name.field-name.attribute
For example:
Employee.firstName.jdbc-type
Column attributes are described in Table A–95.
Also allows you to set the use-unique-table-names property.
If true, this property specifies that generated table names
are unique within each application server domain. The default is false.
For further information and an example, see schema-generator-properties.
|
The following options of the asadmin deploy or asadmin deploydir command control the automatic creation of database
tables at deployment:
Table 7–4
asadmin
deploy and
asadmin deploydir Generation Options
|
Option
|
Default
|
Description
|
|
--createtables
|
none
|
If true, causes database tables to be created for
beans that need them. If false, does not create tables.
If not specified, the value of the create-tables-at-deploy attribute
in sun-ejb-jar.xml is used.
|
|
--dropandcreatetables
|
none
|
If true, and if tables were automatically created
when this application was last deployed, tables from the earlier deployment
are dropped and fresh ones are created.
If true, and if tables were not automatically
created when this application was last deployed, no attempt is made to drop
any tables. If tables with the same names as those that would have been automatically
created are found, the deployment proceeds, but a warning indicates that tables
could not be created.
If false, settings of create-tables-at-deploy or drop-tables-at-undeploy in the sun-ejb-jar.xml file are overridden.
|
|
--uniquetablenames
|
none
|
If true, specifies that table names are unique within
each application server domain. If not specified, the value of the use-unique-table-names property in sun-ejb-jar.xml is
used.
|
|
--dbvendorname
|
none
|
Specifies the name of the database vendor for which tables are created.
Allowed values are db2, mssql, oracle, derby, and sybase,
case-insensitive.
If not specified, the value of the database-vendor-name attribute
in sun-ejb-jar.xml is used.
If no value is specified, a connection is made to the resource specified
by the jndi-name subelement of the cmp-resource element in the sun-ejb-jar.xml file, and the
database vendor name is read. If the connection cannot be established, or
if the value is not recognized, SQL-92 compliance is presumed.
|
If one or more of the beans in the module are manually mapped and you
use any of the asadmin deploy or asadmin deploydir options, the deployment is not harmed in any way, but the options
have no effect, and a warning is written to the server log.
If the deploytool mapped one or more of the beans, the --uniquetablenames option of asadmin deploy or asadmin
deploydir has no effect. The uniqueness of the table names was established
when deploytool created the mapping.
The following options of the asadmin undeploy command
control the automatic removal of database tables at undeployment:
Table 7–5
asadmin
undeploy Generation Options
|
Option
|
Default
|
Description
|
|
--droptables
|
none
|
If true, causes database tables that were automatically
created when the bean(s) were last deployed to be dropped when the bean(s)
are undeployed. If false, does not drop tables.
If not specified, the value of the drop-tables-at-undeploy attribute in sun-ejb-jar.xml is used.
|
For more information about the asadmin deploy, asadmin deploydir, and asadmin undeploy commands, see the Sun Java System Application Server Platform Edition 8.2 Reference Manual.
When command line and sun-ejb-jar.xml options are
both specified, the asadmin options take precedence.
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