---
sourceDocument: Yokohama Build or modify applications
sourceDocumentLink: https://www.servicenow.com/docs/r/yokohama/application-development

 Release :

    - yokohama

ft:locale :

    - en-US

ft:publication_title :

    - Yokohama Build or modify applications

ft:clusterId :

    - cadev

bundleId :

    - cadev

workflow :

    - Development, Data, and Analytics


---

# Add joins between ERP tables

# Add joins between ERP tables {#ariaid-title1}

* Release version: Yokohama
* 
* Updated January 30, 2025
* 
* ![](https://www.servicenow.com/docs/portal-asset/ico-clock) 2 minutes to read

Link multiple ERP (Enterprise Resource Planning) tables from the system of record to build an ERP model in ERP Canvas using table joins.

## Before you begin

Table joins require a read operation that uses table read entities. For more information, see [Add an operation to a model in ERP Canvas](https://www.servicenow.com/docs/saZrY7JVkAiS~AmNV8z3rw "Add an operation to an ERP (Enterprise Resource Planning) model in ERP Canvas to define how it retrieves data from or writes data to the ERP system, or creates a new instance of the business object.").  
When you add table joins, the parent table is the first table listed on the Manage entities tab of the ERP model manager page. Child tables pull information from the parent table.  
Note:  
* If you have more than one table for an operation, you must join the tables.
* You can create table joins only for table read operations, not for operations that use a BAPI (Business Application Programming Interface).
{#erp-canvas-add-join-data-model__ul_gr4_wdm_gbc}

Role required: sn_erp_integration.erp_admin, sn_erp_integration.erp_user

## About this task

Table joins link different tables through shared fields. Joins enable you to access data from multiple tables based on logical relationships between them. The relationship can be conditional, which you
specify using join conditions.

Join fields defines the common attribute or key used to connect records in a child table with their corresponding parent records.

## Procedure

1. Navigate to AllERP CanvasERP Canvas Home.
2. Open the ERP model page by selecting the ERP model icon (![ERP model icon]()) in the side panel.
3. Select the model that you want to add a join to.
4. Select the Manage model button.
5. Select the Read operation that you're adding the table join to.
6. **Optional:** Add the tables to join as Table read operation entities if they haven't yet been added to the model.  
   For more information, see [Add a read, update, or create entity to a model in ERP Canvas](https://www.servicenow.com/docs/D95uvrIJ22NNM_wEBVYGew "Specify the operation entity, which is the table or BAPI (Business Application Programming Interface) that ERP Canvas uses for read, update, or create operations.").

7. Rearrange the tables on the Manage entities tab to place the parent table for the join as the first table listed on the ERP model manager page.  
   Important:  
   Reordering deletes any existing table joins for the reordered entities.
   1. Select the Rearrange order button.
   2. Drag the tables to the order that you want, with the parent table as the first table listed on the page.
   3. Select the Confirm reorder button.
   {#erp-canvas-add-join-data-model__substeps_af1_cc2_bbc}
8. Select the Specify inputs tab, which is where you update input parameters to specify table join as a parameter.  
   The input parameters for each table appear.
9. Create a table join parameter.
   1. Find the parameter that will be the parent join field in the Output parameters section and note its name.
   2. Add a new mapped field row in the table by selecting the add (+) icon.
   3. Enter or select the parent join Field name in the new field row.
   4. Select Join from the Type field.  
      The value in the child table Mapped value field updates automatically with the joined field name.

      For example, in the SAP Material Stock model, you can specify
      Material as the parent field in the Field name field, and join it to the material ID by entering <kbd class="ph userinput">mard_material_matnr</kbd> in the parent
      Mapped value field.
   5. Select Save.

   {#erp-canvas-add-join-data-model__substeps_vnx_md2_bbc}  
   Figure 1. Table join fields
10. **Optional:** Add or update any output parameters as needed in the Output parameters section.  
    The joined parameter that you added to as an input is automatically added to the Choose output tab.

    For more information, see [Choose output parameters for an ERP model](https://www.servicenow.com/docs/OX_LJNB6x0Te4D7FgWIe_g "Specify output parameters for an ERP (Enterprise Resource Planning) system read or update operation in ERP Canvas to define how fields and parameters are mapped from the ERP system to the ServiceNow AI Platform. Output parameters also define how returned data is stored on the ServiceNow AI Platform.").

## Result

After you're done creating table joins, you can specify where the returned ERP data goes, and build flows that retrieve and output the data. For more information, see the following topics:

* [Specifying where the ERP system data is saved](https://www.servicenow.com/docs/y6yHgqQUD1byLYl5FFdRzA "Data that ERP Canvas retrieves from ERP (Enterprise Resource Planning) systems can be used in remote tables, extraction tables, and added to flows as data pills in Workflow Studio.")
* [Building flows to read or update the ERP system](https://www.servicenow.com/docs/NdbNUiPnlKTbiurxTBkbMA "After you configure an operation in ERP Canvas, you can build a flow in Workflow Studio to specify details for querying the ERP (Enterprise Resource Planning) system. For example, build a flow that filters by Order ID.")
{#erp-canvas-add-join-data-model__ul_iqy_f32_bbc}

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