VDB Definition - Teiid 8.4

A VDB or virtual database definition is contained in an XML file. For .vdb archive files created in the design tool, this file is embedded in the archive and most fields can be updated through tooling. The XML schema for this file can be found in the docs/teiid/schema directory.

Example VDB XML

<vdb name="${vdb-name}" version="${vdb-version}">

    <!-- VDB properties -->
    <property name="${property-name}" value="${property-value}" />

    <!-- UDF defined in an AS module,  see Developers Guide --> 
    <property name ="lib" value ="{module-name}"></property>

    <import-vdb name="..." version="..." import-data-policies="true|false"/>

    <!-- define a model fragment for each data source -->
    <model visible="true" name="${model-name}" type="${model-type}" >

        <property name="..." value="..." />

        <source name="${source-name}" translator-name="${translator-name}" connection-jndi-name="${deployed-jndi-name}">

        <metadata type="${repository-type}">raw text</metadata>

    </model>

   <!-- define a model with multiple sources - see Multi-Source Models -->
   <model name="${model-name}" path="/Test/Customers.xmi">
        <property name="multisource" value="true"/>
        . . .
        <source name="${source-name}"
            translator-name="${translator-name}" connection-jndi-name="${deployed-jndi-name}"/>
        <source . . . />
        <source . . . />
    </model>

    <!-- see Reference Guide - Data Roles -->
    <data-role name="${role-name}">
        <description>${role-description}</description>
        ….
    </data-role>

    <!-- create translator instances that override default properties -->
    <translator name="${translator-name}" type="${translator-type}" />

        <property name="..." value="..." />

    </translator>
</vdb>

VDB Element

Attributes

name
The name of the VDB. The VDB name referenced through the driver or datasource during the connection time.

version
The version of the VDB (should be an positive integer). This determines the deployed directory location (see Name), and provides an explicit versioning mechanism to the VDB name.

Property Elements

cache-metadata
Can be "true" or "false". defaults to "false" for -vdb.xml deployments otherwise "true". If "false", Teiid will obtain metadata once for every launch of the vdb. "true" will save a file containing the metadata into the PROFILE{{/data/teiid}} directory

query-timeout
Sets the default query timeout in milliseconds for queries executed against this VDB. 0 indicates that the server default query timeout should be used. Defaults to 0. Will have no effect if the server default query timeout is set to a lesser value. Note that clients can still set their own timeouts that will be managed on the client side.

lib
Set to a list of modules for the vdb classpath for user defined function loading. See also Support for User-Defined Functions (Non-Pushdown).

import-vdb Element

Attributes

name
The name of the VDB to be imported.

version
The version of the VDB to be imported (should be an positive integer).

import-data-policies
Optional attribute to indicate whether the data policies should be imported as well. Defaults to "true".

Model Element

Attributes

name
The name of the model is used as a top level schema name for all of the metadata imported from the connector. The name should be unique among all Models in the VDB and should not contain the '.' character.

version
The version of the VDB (should be an positive integer). This determines the deployed directory location (see Name), and provides an explicit versioning mechanism to the VDB name.

Source Element

A source is a named binding of a translator and connection source to a model.

name
The name of the source to use for this model. This can be any name you like, but will typically be the same as the model name. Having a name different than the model name is only useful in multi-source scenarios. In multi-source, the source names under a given model must be unique. If you have the same source bound to multiple models it may have the same name for each. An exception will be raised if the same source name is used for different sources.

translator-name
The name or type of the Teiid Translator to use. Possible values include the built-in types (ws, file, ldap, oracle, sqlserver, db2, derby, etc.) and translators defined in the translators section.

connection-jndi-name
The JNDI name of this source's connection factory. There should be a corresponding "-ds.xml" file that defines the connection factory in the JBoss AS. Check out the deploying VDB dependencies section for info. You also need to deploy these connection factories before you can deploy the VDB.

Property Elements

importer.<propertyname>
Property to be used by the connector importer for the model for purposes importing metadata. See possible property name/values in the Translator specific section. Note that using these properties you can narrow or widen the data elements available for integration.

Metadata Element

The optional metadata element defines the metadata repository type and optional raw metadata to be consumed by the metadata repository.

type
The metadata repository type. Defaults to INDEX for Designer VDBs and NATIVE for non-Designer VDB source models. For all other deployments/models a value must be specified. Built-in types include DDL, NATIVE, INDEX, and DDL-FILE. The usage of the raw text varies with the by type. The raw text is not used with NATIVE and INDEX (only for Designer VDBs) metadata repositories. The raw text for DDL is expected to be be a series of DDL statements that define the schema - see also DDL Metadata. DDL-FILE (used only with zip deployments) is similar to DDL, except that the raw text specifies an absolute path relative to the vdb root of the location of a file containing the DDL. See also Custom Metadata Repository.

Translator Element

Attributes

name
The name of the the Translator. Referenced by the source element.

type
The base type of the Translator. Can be one of the built-in types (ws, file, ldap, oracle, sqlserver, db2, derby, etc.).

Property Elements

Set a value that overrides a translator default property. See possible property name/values in the Translator specific section.