You can export all of your data in Salesforce as frequently as once a week via the Data Export functionality. When you schedule a Data Export, Salesforce generates a zip file that contains a separate .csv file for each object's records in your org that you specified to export. You can select to export either all data for all objects, or select specific objects. In this lesson, I demonstrate the process of creating a scheduled weekly data export.
The Data Import Wizard supports a handful of standard objects in Salesforce and you can leverage it to work with up to 50,000 records.
You can download the Fortune 500 CSV file mentioned in this lesson by going here - https://kartrausers.s3.amazonaws.com/mikewheelermedia/1748709_1534139041905For...
If you need to load more than 50,000 records in Salesforce, then the Data Loader is your tool of choice. In this lesson, we look at installing and using the Data Loader. We also address when to use the Data Import Wizard vs. the Data Loader.
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Export and Import with Data Management Tool...
An important distinction to grasp is the difference between data and metadata as it relates to Salesforce. In this lesson we address what data is as well as what exactly metadata is - and why you should care.