N/query Module
Component.joinTo()
Method Description: Creates an explicit directional join relationship to another component from this component (a polymorphic join). This method sets the Component.target property on the returned query.Component object. Use the method query.create(options) to create your initial query definition (query.Query). The initial query definition uses one query type. For available query types, see query.Type. After you create the initial query definition, use this method to create explicit directional joins to other components from this component. The N/query module supports the same record types that are supported by the SuiteAnalytics Workbook interface. For more information, see Available Record Types.
Returns: query.Component
Supported Script Types: Client and server scripts For more information, see SuiteScript 2.0 Script Types.
Governance: None
Module: N/query Module
Parent Object: query.Component
Sibling Object Members: Component Object Members
Since: 2018.2
Search NetSuite - https://system.netsuite.com/app/help/helpcenter.nl?search=Component.joinTo(options)

// Code Example 1

// Add additional code

//...

var myTransactionQuery = query.create({

    type: query.Type.TRANSACTION

});



var myEntityJoin = myTransactionQuery.joinTo({

    fieldId: 'entity',

    target: query.Type.CUSTOMER

});



myTransactionQuery.columns = [

    myEntityJoin.createColumn({

        fieldId: 'subsidiary'

    })

];



myTransactionQuery.sort = [

    myTransactionQuery.createSort({

        column: myTransactionQuery.columns[0],

        ascending: false

    })

];



var results = myTransactionQuery.runPaged({

    pageSize: 10

});

//...

// Add additional code



//SOURCE: https://system.netsuite.com/app/help/helpcenter.nl?fid=section_1530818855.html