title: How to make a query with PostgreSQL and TypeORM) where a Table has a JSON Type Column
body: <p>How can I query from a JSON-type Column in PostgreSQL? Let's say following is my Entity witch contains the JSON-type column validDates:</p>
  <pre><code>// My Menu - Entity Class
  @Entity()
  export Class Menu {
    @PrimaryGeneratedColumn('uuid')
       id: string;
    @Column('json', {nullable: true})
      validDates?: ValidDatesClass;
  }
  
  // The ValidDatesClass
  export class ValidDatesClass {
     [key: string]: boolean;
  }
  </code></pre>
  <p>And I want to retrieve (SQL syntax) all Menus where validDates 's value is true (example of a validDates- entry: &quot;Mon Aug 01 2018&quot;: true )</p>