Stage related multiples Sources

• When the entities are in different databases, the data source for each entity must be specified in the stage configuration.
• This is done through the "condition" property, which is an expression that is evaluated for each entity and if true, the specified data source is used.
• Source conditions are evaluated in the order they are found in the stage, so if an entity meets the two-source condition, the data source from the first source that meets the condition will be used.

Stage related to multiple Sources sharing the mapping

This schema has two entities that are in different databases.

The database attribute is used in the entity to be able to specify that an entity is in a database other than the default of the schema.

domain:
  entities:
    - name: Countries
      primaryKey: ["iso3"]
      uniqueKey: ["name"]
      properties:
        - name: name
          required: true
        - name: iso3
          length: 3
          required: true
      relations:
        - name: states
          type: manyToOne
          composite: true
          from: iso3
          entity: States
          to: countryCode
    - name: States
      primaryKey: ["id"]
      uniqueKey: ["countryCode", "name"]
      properties:
        - name: id
          type: integer
          required: true
        - name: name
          required: true
        - name: countryCode
          required: true
          length: 3
      relations:
        - name: country
          from: countryCode
          entity: Countries
          to: iso3
infrastructure:          
  sources:
    - name: dataSource1
      dialect: MySQL
      connection:
        host: localhost
        port: 3306
        user: test
        password: test
        database: test
    - name: dataSource2
      dialect: PostgreSQL
      connection:
        host: localhost
        port: 5432
        user: test
        password: test
        database: test
  stages:
    - name: stage1
      sources:
        - name: dataSource2
          condition: entity == "States"
        - name: dataSource1

Environment Variables:

CNN_MYSQL={"host":"localhost","port":3306,"user":"test","password":"test","database":"test"}
CNN_POSTGRES={"host":"0.0.0.0","port":5433,"user":"test","password":"test","database":"test"}

Stage related to multiple datasources with different mapping

This example poses a stage where two sources are accessed. Data source 1 is mysql and contains the Countries table and source 2 is Postgres contains the States table.

In the case of the Countries entity, both the name of the table and the fields coincide with the name of the entity and the name of the properties, so the mapping is transparent.

But in the case of the States entity, the name of the table and its fields differ, so the mapping defines the mapping.

domain:
  entities:
    - name: Positions
      abstract: true
      properties:
        - name: latitude
          length: 16
        - name: longitude
          length: 16
    - name: Countries
      extends: Positions
      primaryKey: ["iso3"]
      uniqueKey: ["name"]
      properties:
        - name: name
          required: true
        - name: iso3
          length: 3
          required: true
        - name: region
        - name: subregion
      relations:
        - name: states
          type: manyToOne
          composite: true
          from: iso3
          entity: States
          to: countryCode
    - name: States
      extends: Positions
      primaryKey: ["id"]
      uniqueKey: ["countryCode", "name"]
      properties:
        - name: id
          type: integer
          required: true
        - name: name
          required: true
        - name: countryCode
          required: true
          length: 3
      relations:
        - name: country
          from: countryCode
          entity: Countries
          to: iso3
infrastructure:
  mappings:
    - name: mapping1
    - name: mapping2
      entities:
        - name: States
          mapping: TBL_STATES
          properties:
            - name: id
              mapping: ID
            - name: name
              mapping: NAME
            - name: countryCode
              mapping: COUNTRY_CODE
            - name: latitude
              mapping: LATITUDE
            - name: longitude
              mapping: LONGITUDE          
  sources:
    - name: dataSource1
      dialect: MySQL
      mapping: mapping1
      connection: $CNN_MYSQL
    - name: dataSource2
      dialect: PostgreSQL
      mapping: mapping2
      connection: $CNN_POSTGRES
  stages:
    - name: stage1
      sources:
        - name: dataSource2
          condition: entity == "States"
        - name: dataSource1

Laboratories

• CLI - two datasource same query