What is InstallData in Magento2:
InstallData will allow us to insert data into newly create table or existing table on DB. We can also able to insert more than one row into table using InstallData script. using below script am going to insert customer_name , email , mobile_number columns into jute_ecommerce table (with multiple records).
Once script is ready then update your module.xml file with new schema & setup version. And then run upgrade command on terminal.
Ex: root> php bin/magento setup:upgrade
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