Salesforce LWC Lightning Data Table Not Displaying Data : Abhijeet

March 05, 2025 March 05, 2025

Salesforce LWC Lightning Data Table Not Displaying Data
by: Abhijeet
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**Summary of the Content:** In Salesforce, when creating a Lightning Web Component (LWC) with a data table, you may face issues with the data not displaying correctly. This typically happens due to improper mapping of key attributes like ‘data’ and ‘columns’ in your LWC component. Several factors can cause this issue, including incorrect case sensitivity for field names and misconfigurations in the corresponding JavaScript (JS) and HTML files. **Key Steps to Resolve the Issue:** 1. **HTML Component Check:** Ensure the `lightning-datatable` has the correct attributes—`key-field`, `data`, and `columns`. 2. **Column Mapping Verification:** In the JS file, verify that the `fieldName` of each column matches the API field names accurately, keeping case sensitivity in mind. 3. **Apex Class Query Check:** When fetching data using an Apex class, ensure that the SOQL query references valid field names. 4. **@wire Decorator:** Confirm the data is processed correctly through the `@wire` decorator and add debug logs to track data updates. 5. **Meta File Configuration:** Make sure the `meta.xml` file allows visibility of the component in Lightning pages by including appropriate targets. 6. **Deployment:** After applying the fixes, redeploy the component to ensure it displays the data correctly. By following these steps, users can effectively troubleshoot and solve data display issues in the LWC data table. **Conclusion:** This tutorial covers essential troubleshooting techniques for displaying data in an LWC data table in Salesforce. Understanding the nuances of attribute mapping, case sensitivity, and proper component configuration can help in efficiently resolving display issues. **Additional Context:** Lightning Web Components (LWC) are a modern, JavaScript-based framework utilized in Salesforce for building responsive web applications. Ensuring proper data interchange between the server-side (Apex) and client-side (LWC) is crucial for creating dynamic user interfaces. **Relevant Hashtags for SEO:** #Salesforce #LightningWebComponents #LWCDatatable #Apex #WebDevelopment #DataDisplay #SalesforceTutorial #ProgrammingTips #Troubleshooting #TechEducation #DevCommunity

In Salesforce, while creating an LWC Lightning data table, you might encounter an issue with not getting the data in the LWC data table. There are many reasons that restrict the data from displaying record values on the data table.

In this Salesforce tutorial, we will learn to resolve the issue of Salesforce LWC Lightning data table not displaying the data.

Why Is The LWC Data Table Not Showing The Data?

This issue of not getting the data displayed in the LWC data table or any column in the table generally occurs when we fetch the data dynamically through an Apex class or an API callout, when the data table attributes are not correctly mapped.

The lightning-datatable uses two main attributes ‘data‘ and ‘columns‘. If either or both of these are not mapped properly, and not wired using the @wire decorator, then the LWC data table won’t show any data.

Salesforce LWC data table not showing data

The other reasons may relate to invalid column field names, and an issue with case sensitivity is also a reason that the correct value does not return data in the table, unlike Apex, the LWC JavaScript is case sensitive.

Fix The LWC Data Table Not Showing The Data

In the below steps, we will see the code verification of all the files of LWC component that are component.js, component.html, and component.js-meta.xml.

1. Check the HTML file of the LWC component and check whether the lightning-datatable component has ‘key-field‘, ‘data‘, and ‘columns‘ defined and mapped correctly.

The key field is generally ID, and the data should be mapped to the table data that you defined in the JS file.

<template>
  <lightning-card title="LWC Datatable">
    <lightning-datatable
      key-field="Id"
      data={tableData}
      columns={tableColumns}
    ></lightning-datatable>
  </lightning-card>
</template>

2. In the JS file of the LWC component, check the columns array and ensure that the fieldName is correct. The field name here is the API name of the object field that is also included in the controller class to fetch fields.

The field names are case sensitive, so check the values with case sensitivity.

For example, if the field name from Apex is FirstName and you have entered Name, so it won’t fetch data, and entering firstname instead of FirstName won’t display data for that label column due to case sensitivity.

const columns = [
  { label: "Name", fieldName: "Name", type: "text" },
  { label: "Phone", fieldName: "Phone", type: "phone" },
  { label: "Email", fieldName: "Email", type: "email" }
];

3. If you are fetching the table data dynamically via the Apex class, check the SOQL query field values. The field names can be checked from Object Manager > Object > Fields and Relationships, then see the API name of the field. Enter the same API name for the field in the controller class.

public with sharing class ContactController {
  @AuraEnabled(cacheable=true)
  public static List<Contact> getContacts() {
    return [SELECT Id, Name, Phone, Email FROM Contact LIMIT 10];
  }
}

4. To connect LWC components to Salesforce data sources, such as Apex classes, if you are using the @wire decorator instead of an imperative call, ensure the data is processed correctly. For this, we can add a debug log to confirm that the @wire property is updating tableData.

import { LightningElement, wire, track } from 'lwc';
import getContactList from '@salesforce/apex/ContactController.getContacts';

export default class LwcDatatable extends LightningElement {
  @track tableData = [];
  @track tableColumns = [
    { label: "Name", fieldName: "Name", type: "text" },
    { label: "Phone", fieldName: "Phone", type: "phone" },
    { label: "Email", fieldName: "Email", type: "email" }
  ];

  @wire(getContactList)
  wiredContacts({ error, data }) {
    if (data) {
      this.tableData = data;
      console.log('Wired Data:', JSON.stringify(this.tableData));
    } else if (error) {
      console.error('Wired Error:', error);
    }
  }
}

With this debug log, we can confirm that the data is wired correctly and updating accordingly.

5. At last, go to the meta.xml file and enter the code below to make the component visible to the lightning pages. Without this setting, the component won’t appear in the Lightning app builder’s custom components.

<isExposed>true</isExposed>
    <targets>
        <target>lightning__AppPage</target>
        <target>lightning__RecordPage</target>
        <target>lightning__HomePage</target>
    </targets>

6. After making the above changes and fixes, deploy the LWC component to the Lightning page.

Now, the data table will display all the field column data from the columns array of the lightning-datatable.

LWC data table column is not displaying data

This way, we can fix the bug of empty data column and display data in the LWC lightning data table in Salesforce by going through the above fixes.

Conclusion

In this Salesforce tutorial, we learned how to fix the issue of the LWC data table not displaying data. In the above steps, we discussed various checks in the LWC component that can ensure that the data will be displayed on the LWC data table.

Following the code checks discussed above, you can resolve this issue efficiently and display the fetched data in the columns of LWC data table.

Salesforce Reader

Salesforce LWC Lightning Data Table Not Displaying Data : Abhijeet

Why Is The LWC Data Table Not Showing The Data?

Fix The LWC Data Table Not Showing The Data

Conclusion

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