Configuration Reference

Introduction

The configuration is a metadata object that lists all the database entities — such as tables — that the data connector has to know about in order to serve queries. It never changes during the lifetime of the data connector service instance. When your database schema changes you will have to update the configuration accordingly, see updating with introspection.

Structure

The configuration object is a JSON object with the following fields:

{
  "jdbcUrl": "",
  "jdbcProperties": {},
  "schemas": [],
  "tables": [],
  "functions": [],
  "nativeQueries": {}
}

Property: JDBC URL

The JDBC connection URL to connect to the Trino database. This is a required field.

The value can either be a literal string, or a reference to an environment variable:

{
  "jdbcUrl": "jdbc:trino://localhost:8090/xe?user=foo&password=bar",
  "jdbcUrl": { "variable": "TRINO_JDBC_URL" }
}

Property: JDBC Properties

This is a JSON object containing key-value pairs of additional properties to be passed to the JDBC driver. For example, with MySQL to enable running multiple statements in a given query:

{
  "jdbcProperties": { "allowMultiQueries": "true" }
}

Property: Schemas

This is an optional array of schema names to include in the introspection process. If not provided, all schemas will be included.

Example:

{
  "schemas": ["public", "other_schema"]
}

Property: Tables

This is an array of table definitions, generated automatically during introspection.

Example:

{
  "tableName": "Album",
  "tableType": "TABLE",
  "description": "",
  "columns": [
    {
      "name": "AlbumId",
      "description": "",
      "type": "int",
      "numeric_scale": 0,
      "nullable": false,
      "auto_increment": true,
      "is_primarykey": true
    },
    {
      "name": "Title",
      "description": "",
      "type": "varchar",
      "numeric_scale": null,
      "nullable": false,
      "auto_increment": false,
      "is_primarykey": false
    },
    {
      "name": "ArtistId",
      "description": "",
      "type": "int",
      "numeric_scale": 0,
      "nullable": false,
      "auto_increment": false,
      "is_primarykey": false
    }
  ],
  "pks": ["AlbumId"],
  "fks": {
    "FK_AlbumArtistId": {
      "foreign_collection": "Artist",
      "column_mapping": {
        "ArtistId": "ArtistId"
      }
    }
  }
}

Property: Functions

This is an array of function definitions.

Example:

{
  "function_catalog": "public",
  "function_schema": "public",
  "function_name": "add",
  "argument_signature": "(N NUMBER, M NUMBER)",
  "data_type": "TABLE (N NUMBER, M NUMBER)",
  "comment": "Adds two numbers"
}

Property: Native Queries

This is a JSON object containing key-value pairs of Native Queries to be used in the data connector.

Two types of Native Queries are supported: Inline and Parameterized.

Example:

{
  "native_query_inline": {
    "sql": {
      "parts": [
        {
          "type": "text",
          "value": "SELECT 1 AS result FROM DUAL"
        }
      ]
    },
    "columns": {
      "result": {
        "type": "named",
        "name": "INT"
      }
    },
    "arguments": {},
    "description": ""
  },
  "ArtistById_parameterized": {
    "sql": {
      "parts": [
        {
          "type": "text",
          "value": "SELECT * FROM CHINOOK.ARTIST WHERE ARTISTID = "
        },
        {
          "type": "parameter",
          "value": "ARTISTID"
        }
      ]
    },
    "columns": {
      "ARTISTID": {
        "type": "named",
        "name": "INT"
      },
      "NAME": {
        "type": "nullable",
        "underlying_type": {
          "type": "named",
          "name": "STRING"
        }
      }
    },
    "arguments": {
      "ARTISTID": {
        "description": null,
        "type": {
          "type": "named",
          "name": "INT"
        }
      }
    },
    "description": null,
    "isProcedure": false
  }
}

Updating with introspection

Whenever the schema of your database changes you will need to update your data connector configuration accordingly to reflect those changes.

Running update in a configuration directory will do the following:

• Connect to the database with the specified jdbcUrl, and then overwrite all data in the tables field

• Fill in default values for any fields absent from the configuration