org.apache.calcite.schema

Interface SchemaFactory

All Known Implementing Classes:

CloneSchema.Factory, JdbcSchema.Factory, ReflectiveSchema.Factory

public interface SchemaFactory

Factory for Schema objects.

A schema factory allows you to include a custom schema in a model file. For example, here is a model that contains a custom schema whose tables read CSV files. (See the optiq-csv for more details about this particular adapter.)

{
   version: '1.0',
   defaultSchema: 'SALES',
   schemas: [
     {
       name: 'SALES',
       type: 'custom',
       factory: 'org.apache.calcite.adapter.csv.CsvSchemaFactory',
       mutable: true,
       operand: {
         directory: 'target/test-classes/sales'
       },
       tables: [
         {
           name: 'FEMALE_EMPS',
           type: 'view',
           sql: 'SELECT * FROM emps WHERE gender = \'F\''
          }
       ]
     }
   ]
 }
 
 

If you do not wish to allow model authors to add additional tables (including views) to an instance of your schema, specify 'mutable: false'.

A class that implements SchemaFactory specified in a schema must have a public default constructor.

Method Summary

Methods

Modifier and Type	Method and Description
Schema	create(SchemaPlus parentSchema, String name, Map<String,Object> operand) Creates a Schema.

Method Detail

create

Schema create(SchemaPlus parentSchema,
            String name,
            Map<String,Object> operand)

Creates a Schema.

Parameters:

parentSchema - Parent schema

name - Name of this schema

operand - The "operand" JSON property

Returns:

Created schema