Kaizen #199: FAQs on Multi-Select Lookup (MxN) Field in Zoho CRM

Kaizen #199: FAQs on Multi-Select Lookup (MxN) Field in Zoho CRM

 Nearing 200th Kaizen Post – We want to hear from you!
Do you have any questions, suggestions, or topics you would like us to cover in future posts? Your insights and suggestions help us shape future content and make this series better for everyone. 

Hey everybody!!!
Welcome back to another post in the Kaizen series!
In this post, we will address some of the most frequently asked questions about the Multi-Select Lookup(MxN) field from the Zoho CRM developer community forum.

1. What is a Multi-select lookup field?

A multi-select lookup field in Zoho CRM lets you create a many-to-many relationship between two modules. This means a record in one module can be linked to multiple records in another module and vice versa.
For example, using an multi-select lookup field, you can associate multiple skills with an employee.

2. How does the Mutli-Select Lookup relationship work?

When you create a Multi-Select Lookup between two modules, for example, Employees and Skills, Zoho CRM automatically creates a hidden linking module, which is also known as an MxN module. This module stores the associations between records in the two modules, enabling you to track and manage many-to-many relationships.

For instance, if you link Employees and Skills, a linking module named EmpXSkills will be created.

This linking module is accessible only via API.

Backend Flow of multi-select lookup Relationship



In the linking module, two lookup fields (lookup fields with api names - Employees and Skills) will be created. The lookup fields, one pointing to Employees and the other pointing to Skills from the linking module, establish a connection between the linking module and its associated module.

Why you cannot use a lookup field for this use case? 
In Zoho CRM, a lookup field creates a one-to-many relationship between two modules i.e. one record in the source module can be linked to only one record in the target module.

Example :
If you create a lookup field for Skills in the Employees module, each employee can be linked to only one skill. So, use a multi-select lookup field instead of a lookup field when you need to represent complex relationships like one employee - many skills and one skill - many employees.

3. How to create a multi-select Lookup field using Zoho CRM APIs?

To create a Multi-Select lookup field between two modules using Zoho CRM APIs, follow these steps:

Step 1: Identify the Module API Name
Before creating the field, you should know the API names of the Employees and Skills modules. For that, use the Get Module Metadata API.  

Request URL  : {{api-domain}}/crm/v8/settings/modules
Request method : GET



Now, search for the Employees module in the response and note its API name.

Step 2: Use the Create Custom Fields API

To establish a many-to-many relationship between two modules, in our case, Employees and Skills, you need to create a custom field of type multi-select lookup in the Employees module (parent module).  Here, we will associate multiple skills to an employee.

This custom field requires:
  • The related module you want to link to - Skills.
  • A display field from the related module
  • The linking module (EmpXSkills), which stores the actual associations.
Use the Create Custom Fields API to create custom fields.

Request URL : {{api_domain}}/crm/v8/settings/fields?module=Employees
Request method : POST

Sample input :



{
    "fields": [
        {
            "field_label": "Skills", //Name of the field in your module
            "data_type": "multiselectlookup", //Type of the field
            "multiselectlookup": { //This JSON object contains the multi-select lookup relationship details

                "connected_details": { //Details about the module and field you want to link
                    "module": {
                        "api_name": "Skills" //API name of the related module
                    },
                    "field": {
                        "field_label": "Skills" //The field in the related module to display
                    }
                },
                "linking_details": { //Details about the junction or linking module that manages the many-to-many relationship
                    "module": {
                        "plural_label": "EmpXSkills" //Plural label of the junction module
                    }
                }
            }
        }
    ]
}


4. How Do You Find the Linking Module and Field API Names?

To know the API name of the linking module:
Use the Get Modules API and search for "generated_type" : "linking" in the response to identify MxN modules. In our case, EmpXSkills.

Request URL : {{api_domain}}/crm/v8/settings/modules
Request method : GET



To know the field API names in the linking module:
Use the Get Fields Metadata API to retrieve the API names of lookup fields within the linking module.

Request URL : {{api_domain}}/crm/v8/settings/fields?module=EmpXSkills
Request method : GET

5. How do I associate records via a multi-select lookup field using the Insert Records API in Zoho CRM?

To associate records using a multi-select lookup field, you must provide the record IDs from the related module. The association is made through the linking module.

Example :
Associating multiple skills with an employee using the multi-select lookup field.

Request URL : {{api-domain}}/crm/v8/Employees
Request method : POST

Sample input :


{
  "data": [
    {
      "Name": "Patricia",
      "Email": "patricia@mail.com",
      "Position": "Marketing Specialist",
      "Year_of_Experience": 5,
      "Skills": [   // API name of the multi-select lookup field in the Employees module
        {
          "Skills": { // API name of the lookup field in the linking module pointing to the Skills module
            "name": "Marketing",
            "id": "5725767000002149427"  //ID from the Skills module are mandatory to establish the link
          }
        },
        {
          "Skills": {
            "name": "Social Media Marketing",
            "id": "5725767000002149476"
          }
        }
      ]
    }
  ]
}



6. How do I associate an Employee's skills using the linking module in Zoho CRM?

To establish a relationship between the Employees and Skills modules through the linking module, use the Insert Records API to create a record in the linking module, EmpXSkills.

To do this,
  • Use the appropriate lookup field API names to reference the parent module.
  • You must need the record IDs from both the Employees and Skills modules to create the associations.
Request URL : {{api-domain}}/crm/v8/EmpXSkills
Request method : POST

Sample input :


{
  "data": [
    {
      "Name": "Patricia",
      "Employees": {
        "id": "5725767000002161001"  // Record ID from the Employees module
      },
      "Skills": {
        "id": "5725767000002149476"  // Record ID from the Skills module
      }
    }
  ]
}



7. When should I use create/update operations in the Employees module vs the EmpXSkills module?

                Employees Module

               EmpXSkills (linking) Module

Use when you want to create or update an Employee and associate Skills using the Multi-select Lookup field.

Use when you want to create or remove associations between existing Employee and Skill records without modifying the actual Employee or Skill data.

Creating a new employee and assigning their skills at once.

Managing relationships between existing records i.e., linking and unlinking skills to employees.


8. How to update a record in the linking module?

To update a record in the linking module, use the Update Records API.
Request URL : {{api-domain}}/crm/v8/EmpXSkills/5725767000006269044
Request method : PUT

Sample input :


{
    "data": [
        {
            "Skills": {
                "name": "Marketing",
                "id": "5725767000002170035" //Associating another skill with the employee 
            }
        }
    ]
}

In the above sample, we have replaced an existing skill associated with an employee with another Skill in the linking module.This is done by updating the Skills lookup field in the EmpXSkills record.

Please note that in the linking module, Skills is a lookup field, so you can associate only one skill per linking record. But in the Employees module, Skills is a multi-select lookup field, so an employee can be associated with multiple skills.

9. How to unlink records from the parent module as well as the linking module?

Unlink the associated records from the parent module:

Using the Update records API, you can remove an associated skill from an employee, use the "_delete": null key within the multi-select lookup field in the Employee record update.

Request URL : {{api-domain}}/crm/v8/Employees/5725767000006269044
Request method : PUT

Sample input :

{
"data": [
        {
            "Skills": [
               {
                    "Skills": {
                        "name": "Marketing", 
                        "id": "5725767000002170035" // The Skill record you want to unlink
                    },
                    "id": "5725767000007228047", //record ID - The record created in the linking module for the employee with the Marketing skill
                    "_delete" : null 
                }
            ]
        }
    ]
}



Replace an associated record from the linking module:

Use the Update Records API to replace an existing association in the linking module.

Request URL : {{api-domain}}/crm/v8/EmpXSkills/5725767000007228035
Request method : PUT

Sample input :


{
    "data": [
        {
            "Skills": {
                "name": "Java",
                "id": "5725767000005259075" //replacing a new skill 
            }
        }
    ]
}

In the above sample, we have replaced the existing skill with Java.

10. Why am I seeing the error "DUPLICATE_LINKING_DATA"  in the Update Records API

This error occurs when you try to associate records with the parent record that are already linked with the Multi-select lookup field. To resolve this, check the records you are trying to link and make sure your association is only with records that are not already linked.

Know your existing linked records:

Before the Update Records API, use the Get Related Records Data API and search for the multi-select lookup field. In our case, Skills is the multi-select lookup field created in the Employees module. This will return all records already associated.

Example :


The response returns all Skills already linked with that Employee.

Using this way, compare the IDs from the API response with the new records you are about to link, and only proceed with non-duplicate IDs. This avoids duplicate entries and prevents the "DUPLICATE_LINKING_DATA" error.

11. What happens if I delete a record in the linking module?

When you delete a record in the linking module, it only removes the association between the related records in the Employees and Skills modules.

Note :
  • Deleting a linking module record removes only the relationship between two records from the Employees and Skills modules.
  • Deleting an Employee or Skill record deletes all corresponding entries in the linking module as well.

12. How do I query linked records?

Use the COQL API to query multi-select lookup data by specifying the corresponding linking module's API name directly in your query. The linking module is treated as a separate module in Zoho CRM, so you can retrieve associated records by querying it like any other module.

Sample query :


{
  "select_query": "select Skills.Name as skill, Employees.Name as employee from EmpXSkills where Skills.Name like '%Marketing%'"
}


Use the Get Module Metadata API to know the linking module's API name.

13. How do I export multi-select lookup records using the Bulk Read API?

To export multi-select lookup data, linking module records efficiently, use the Bulk Read API with the linking module’s API name.

Request method : POST

Sample Request :


{
    "callback": {
        "method": "post"
    },
    "query": {
        "module": {
            "api_name": "EmpXSkills" //API name of the linking module
        },
        "fields": [
            "Employees.Name",
            "Employees.Year_of_Experience",
            "Skills.Name"
        ],
        "criteria": {
            "group": [
                {
                    "field": {
                        "api_name": "Employees.Year_of_Experience" 
                    },
                    "comparator": "greater_than",
                    "value": "4"
                },
                {
                    "field": {
                        "api_name": "Skills.Name"
                    },
                    "comparator": "contains",
                    "value": "Social"
                }
            ],
            "group_operator": "AND"
        }
    }
}


14. Can I import my linking module's data using the Bulk Write API?

Yes. Like the Leads and Contacts modules, you can also import linking module's data into Zoho CRM using the Bulk Write API by directly specifying the linking module’s API name.

If you are importing data that involves both a parent module, Employees and its associated MxN linking module, follow these steps:

1. Create separate CSV files:
  • One for the parent module - Employees
  • One for the linking module - EmpXSkills
2. Zip the files into a single ZIP file.
3. Upload the ZIP in a single Bulk Write API request.
4. Ensure accurate field mappings are provided in the API request body.

Refer to Kaizen #131 - Bulk Write for parent-child records using Scala SDK for more details on handling parent-child records.


15. Can I receive notifications if a multi-select lookup field in a module is modified or updated?

Yes, you can receive notifications when a MxN field is updated using the Notification API. To enable instant notifications for actions performed in a module, use the respective API names of the linking module in the input body.

Request method : POST

Sample input :


{
    "watch": [
        {
            "channel_id": "10000",
            "events": [
                "EmpXSkills.all"  //EmpXSkills represents the API name of the linking module
            ],
            "return_affected_field_values": true  
        }
    ]
}


16. Can I use criteria-based filtering when accessing multi-select lookup data using the Search API?

Yes, you can filter multi-select lookup data using the criteria parameter in the Search API's URL.

Here is an example that fetches records from the EmpXSkills linking module.

Request URL : {{api-name}}/crm/v8/EmpXSkills/search?criteria=((Secondary_Email:equals:patricia@mail.com)and(Skills:equals:Content_Marketing))
Request method : GET

Sample response :



                                                                                                                               x-----------------------------x


We trust that this post meets your needs and is helpful. Let us know your thoughts in the comment section or reach out to us at support@zohocrm.com 

Stay tuned for more insights in our upcoming Kaizen posts!


Other FAQs in the Kaizen series :


    • Sticky Posts

    • Kaizen #226: Using ZRC in Client Script

      Hello everyone! Welcome to another week of Kaizen. In today's post, lets see what is ZRC (Zoho Request Client) and how we can use ZRC methods in Client Script to get inputs from a Salesperson and update the Lead status with a single button click. In this
    • Kaizen #222 - Client Script Support for Notes Related List

      Hello everyone! Welcome to another week of Kaizen. The final Kaizen post of the year 2025 is here! With the new Client Script support for the Notes Related List, you can validate, enrich, and manage notes across modules. In this post, we’ll explore how
    • Kaizen #217 - Actions APIs : Tasks

      Welcome to another week of Kaizen! In last week's post we discussed Email Notifications APIs which act as the link between your Workflow automations and you. We have discussed how Zylker Cloud Services uses Email Notifications API in their custom dashboard.
    • Kaizen #216 - Actions APIs : Email Notifications

      Welcome to another week of Kaizen! For the last three weeks, we have been discussing Zylker's workflows. We successfully updated a dormant workflow, built a new one from the ground up and more. But our work is not finished—these automated processes are
    • Kaizen #152 - Client Script Support for the new Canvas Record Forms

      Hello everyone! Have you ever wanted to trigger actions on click of a canvas button, icon, or text mandatory forms in Create/Edit and Clone Pages? Have you ever wanted to control how elements behave on the new Canvas Record Forms? This can be achieved
    • Recent Topics

    • Bulk Fill In & Edit PO/Bill/SO/Invoice

      Hello, I am adding stock in bulk on a PO, the system is automatically populating the Rate (price) and Tax from the item data. Problem is that the bill rate is different from the rate on the item data, so I have to manually erase each and enter the price.
    • Separate Items & Services

      Hi, please separate items and services into different categories. Thank you
    • Items Below Reorder Point Report?

      Is there a way to run a report of Items that are below the Reorder Point? I don't see this as a specific report, nor can I figure out how to customize any of the other stock reports to give me this information. Please tell me I'm missing something s
    • Allocating inventory to specific SO's

      Is there a way that allocate inventory to a specific sales order? For example, let's say we have 90 items in stock. Customer 1 orders 100 items. This allocates all 90 items to their order, and they have a back order for the remaining 10 items which could
    • Cancelled Transfer order problem

      Hello, We've canceled a transfer order, and we can't add the related items to a new Transfer Order. The system tells us that the bin doesn't have the required quantity, but when we check the item, it indicates that there are 2 units in the bin. It also
    • Creating a Chart from a Report

      In Zoho Analytics, is it possible to create a chart from a Pivot View report? We are looking to use Zoho Analytics to replace Excel for Sales reports and would like to be able to show both the table and the chart together.
    • Client Portal ZOHO ONE

      Dear Zoho one is fantastic option for companies but it seems to me that it is still an aggregation of aps let me explain I have zoho books with client portal so client access their invoice then I have zoho project with client portal so they can access their project but not their invoice without another URL another LOGIN Are you planning in creating a beautiful UI portal for client so we can control access to client in one location to multiple aps at least unify project and invoice aps that would
    • Email Insights included in Bigin emals are marked as SPAM everywhere

      Today I noticed that email recipients who use Office 365 never receive emails sent from Bigin. Further examination showed that all Email Insights links in email headers are marked as spam/phishing by Office 365. Example screen included. The problem is
    • Data Import | Zoho Analytics Custom Query Window Size

      Please increase the window size for the Custom Query Data Import. It's impossible to work with such a small query window.
    • Name changed in settings for mailbox but still not changed when typed in To field

      In the email account secretary@ i have updaetd the new staff members details but the old members name still appears when I type secretary@ in the To field. I cant work out where Zoho is finding the old name from. I have deleted the browser cache. If I
    • Cannot add my name to my domain name

      I want to have My name@mydomain.com and it says my name is linked to another account already. Please fix it since I do not have another account.
    • Invoice status on write-off is "Paid" - how do I change this to "Written off"

      HI guys, I want to write off a couple of outstanding invoices, but when I do this, the status of the invoices shows as "Paid". Clearly this is not the case and I need to be able to see that they are written off in the customer's history. Is there a way
    • Establishing new Zoho email account on laptop

      Good Morning: I am very long time Outlook business user and decided to try your email service last night and had established an account. I am trying to verify my account; how do I establish my Zoho email account on my laptop? I opened the account with
    • unable to send message reason 550 5.4.6 unusual sending activity

      My email account can't send message. It shows unable to send message reason 550 5.4.6 unusual sending activity detected
    • how to add email to existing organization i w

      I am already registered my organization and i have an email id. I need one more email id but i can't find anywhere .i want the cheapest email id . how to add ?
    • e-mail bloqueado

      Estou com meu e-mail lucas@peplus.me bloqueado, preciso desbloquear para retorno de usos em minhas atividades.
    • zoho labels api not working

      We're using n8n to automte email reply using zoho api. I'm facing issue with label api. I added the required scopes but its not working. i followed zoho api documentation but didn't work. also, where do i find/how do i create zoho oauth token mentioneeed
    • Desk DMARC forwarding failure for some senders

      I am not receiving important emails into Desk, because of DMARC errors. Here's what's happening: 1. email is sent from customer e.g. john@doe.com, to my email address, e.g info@acme.com 2. email is delivered successfully to info@acme.com (a shared inbox
    • Streams/Shared email doesn't show up in windows trident app. It works fine on MAC. Is there any difference between 2 install ?

      I can see streams/share email boxs on my MAC version of trident app but i can't see them in windows version of trident app. Is there any difference between 2 install? I try to find setting but not able to see any setting to add stream/share email boxes.
    • add zoho account

      How to add a zoho mail to previous zoho account? I have two
    • Zoho Desk Mobile App Year-End Roundup - 2025

      Dear Zoho Desk users, Greetings! As you gear up for the festive season, we are excited to share a quick journey into all that is released in 2025! Zia's generative AI capabilities Zia insights can be highly beneficial in helping agents manage daily support
    • Narrative 17: The role of Zia AI in customer support

      Behind the scenes of a successful ticketing system: BTS Series Narrative 17: The role of Zia AI in customer support Overview Zia in Zoho Desk is a layered AI assistant that combines generative AI, prediction, and automation to support agents, automate
    • Domain Transaction

      I have purchased a domain name called trainedworkforce.co.in I made the payment got the receipt but the domain is still not purchased after successful transaction .
    • Ability to Set a Unified Tab Order/View for All Users in Zoho Projects

      Hello Zoho Projects Team, We hope you are doing well. We would like to submit a feature request regarding tab/menu organization in Zoho Projects. Current Behavior: The tab (module) order in Zoho Projects is user-specific. Each user (internal or external)
    • Zohomail - The "All Messages" vs "In Box"

      Why do some new email message appear under the all messages view but not in my inbox? That's really annoying but to be fair I've experienced the same with gmail.
    • error while listing mails

      I can't access email in any of my folders: Oops, an error occurred - retry produces the second error response: error while listing mails (cannot parse null string). I've signed in and out of Zoho, restarted my iMac.
    • Introducing the Zoho Projects Learning Space

      Every product has its learning curve, and sometimes having a guided path makes the learning experience smoother. With that goal, we introduce a dedicated learning space for Zoho Projects, a platform where you can explore lessons, learn at your own pace,
    • Where to show Customization Field ?

      Dear Sir, I have made some New Field in Item Field Customisation. Now I don't require that field in Estimate, Sales Orders etc. I just wants that field in Sales Invoice to Show/Hide... Is that possible ?
    • Zoho Desk 2025 round-up: Key highlights on feature releases

      Hello everyone, As we gear up for 2026, here is a detailed round-up of all feature releases in Zoho Desk web throughout the year. For consolidated information on releases check out the What’s New page You can also watch these webinars. Zia in web Zia
    • Print Sales Orders, Purchase Orders or Invoices from API

      Hello, Is it possible to use the print option that is available in Sales Orders Purchase Orders and Invoices with the API?. I don't see any information in the docs about this. Thanks
    • How to show a hided report??

      in CRM Report , I clicked Hide incidently , how to show the floder again? Nowhere I can find the hided report floder...
    • Converting Customer Invoice to Purchase Bill

      Hi, In my service-based business, I sometimes create the customer invoice first, and later I receive the purchase bill from the vendor for the same job. Is there any option in Zoho Books to: Convert a customer invoice into a purchase bill, or Link/associate
    • Email tracking inquiry

      I am trying to track when my emails are opened and clicked like I previously did in HubSpot. HubSpot pretty much did the entire process automatically. After digging through, I finally found in settings --> emails --> BCC Dropbox there is an email I can
    • Mass Update of Lookup Fields not possible

      Hello List I've created a custom field for Leads and Contacts 'Current Campaign'. This is very Handy as I can filter leads and then related them to a campaign. Everything ready, but then I realized that mass update doesn't work for lookup fields... a
    • Collapsible Sections & Section Navigation Needed

      The flexibility of Zoho CRM has expanded greatly in the last few years, to the point that a leads module is now permissible to contain up to 350 fields. We don't use that many, but we are using 168 fields which are broken apart into 18 different sections.
    • Quick Create needs Client Script support

      As per the title. We need client scripts to apply at a Quick Create level. We enforce logic on the form to ensure data quality, automate field values, etc. However, all this is lost when a user attempts a "Quick Create". It is disappointing because, from
    • Download Attached Files

      Hi everyone, Brand new to Zoho Creator.  I have a form with a subform. The subform has a field for "File Upload"   I have this in a subform to allow multiple files to be uploaded to the parent form. Once the files are uploaded, how can i download or view them?   Is this a setting I am just not seeing? If there isn't a way to download them, could i create another form field that dynamically creates the file's URL?  That way a user can click the URL to get to the file? Any help with this would be greatly
    • Ticket layout based on field or contact

      Hi! I want to support the following use-case: we are delivering custom IT solutions to different accounts we have, thus our ticket layouts, fields and languages (priority, status field values should be Hungarian) will be different. How should I setup
    • No funcionan correctamente el calculo de las horas laborales para informe de tickets

      Hola, estoy intentando sacar estadísticas de tiempo de primera respuesta y resolución en horario laboral de mis tickets, pero el calculo de horas en horario laboral no funciona correctamente cree los horarios con los feriados : Ajusté los acuerdos de
    • Zoho Mail Android app update: Set out of office response exclusively for organization members and external users, response interval

      Hello everyone! We have now introduced an option to configure out of office messages exclusively for organization members and external users within the Zoho Mail app. Additionally, now you can also customize response intervals for the Out of office messages.
    • Next Page