Representing Data Sources and Database Schemas in XML

Data sources and database schemas are declared under the dataSources element. A data source for a Domain is declared using jdbcDataSource and a data source for a Topic is declared using jrQueryDataset.

dataSources

The dataSources element is a container for the jdbcDataSource element. A Domain can only have at most one data source. dataSources is a child of the top-level schema element.

dataSources is not required for schemaless JDBC databases such as MySQL unless you are using an attribute for the database schema name.

Child Elements

One of the following elements is required for dataSources. Only one of these can be declared.

jdbcDataSource

The jdbcDataSource element declares a data source for a Domain and is a container for the schemaMap elements used in the Domain. jdbcDataSources does not directly reference a data source in the repository; instead, the actual link to the repository data source is attached as metadata to the Domain design in the repository.

For Topics, use jrQueryDataset. There can only be one jrQueryDataset or jdbcDataSource element in a Domain design file.

jdbcDataSource Hierarchy

The following hierarchy is used to represent JDBC data sources and their database schemas. This hierarchy is under the schema element.

  <dataSources> (1)
    <jdbcDataSource> (1)
      <schemaMap> (1...n)
        <entry> (1)
          <string> (1)

Child Elements

XML Attributes

schemaMap

The schemaMap element is a container for entry elements that represent database schemas used in the Domain.

Child Elements

entry

The entry element in the schemaMap element declares a database schema for use in the Domain. The actual name of the schema is the value of the string child element, while the identifier used in the Domain is set as the key attribute.

If key is set to defaultSchema, the entry element is used to define the default schema.

Child Elements

XML Attributes

string

The string element in the schemaMap hierarchy is a string defining the database schema to be used in the Domain. The string can be one of the following:

Default Schema

If the key attribute of the parent entry element is set to defaultSchema, then entry/string declares the default schema for the Domain. The default schema is a fallback schema name that is substituted when a schema name is missing or not available. This can happen, for example, if you are using a JasperReports Server attribute for the data source or schema. It can also happen if you change the data source for some reason. You can only define one default schema for a database.

Examples

The following example shows a declaration of a data source and two schemas. Note that the data source name in the Design file does not need to be linked to the data source in the repository. That linkage is done outside of the Domain design file.

  <dataSources>
    <jdbcDataSource id="myDataSource">
      <schemaMap>
        <entry key="schema_1">
          <string>schema.1</string>
        </entry>
        <entry key="_234schema">
          <string>1234schema</string>
        </entry>
      </schemaMap>
    </jdbcDataSource>
  </dataSources>

The following example shows a file that uses an attribute for the database schema name, and sets a default schema name to use when the attribute is null.

  <dataSources>
    <jdbcDataSource id="dsFoodMart">
      <schemaMap>
        <entry key="_attribute_schemaAttr_">
          <string>{attribute('schemaAttr')}</string>
        </entry>
        <entry key="defaultSchema">
          <string>public</string>
        </entry>
      </schemaMap>
    </jdbcDataSource>
  </dataSources>

jrQueryDataset

The jrQueryDataset element declares the data source for a Topic. jrQueryDataset does not directly reference a data source in the repository; instead, the actual link to the repository data source is attached as metadata to the Domain design in the repository. There can only be one jrQueryDataset or jdbcDataSource element in a Domain.

jrQueryDataset does not support schemas. For more information about Topics, see the JasperReports Server User Guide.

Element Hierarchy for jrQueryDataset

The following hierarchy is used to represent JDBC data sources and their database schemas. This hierarchy is under the schema element.

  <dataSources> (1)
    <jrQueryDataset> (1)

XML Attributes