comment out or remove line 20 to 31 in map.xml file,
<!-- <ignore>
<document>sales_flat_creditmemo_grid</document>
</ignore>
<ignore>
<document>sales_flat_invoice_grid</document>
</ignore>
<ignore>
<document>sales_flat_order_grid</document>
</ignore>
<ignore>
<document>sales_flat_shipment_grid</document>
</ignore> -->
Add inside <document_rules>
tag of source tag,
<rename>
<document>sales_flat_order_grid</document>
<to>sales_order_grid</to>
</rename>
<rename>
<document>sales_flat_invoice_grid</document>
<to>sales_invoice_grid</to>
</rename>
<rename>
<document>sales_flat_creditmemo_grid</document>
<to>sales_creditmemo_grid</to>
</rename>
<rename>
<document>sales_flat_shipment_grid</document>
<to>sales_shipment_grid</to>
</rename>
Add below content under <field_rules>
tag of source tag.
<move>
<field>sales_flat_creditmemo_grid.grand_total</field>
<to>sales_creditmemo_grid.order_base_grand_total</to>
</move>
<!-- source table custom grid field-->
<ignore>
<field>sales_flat_invoice_grid.base_grand_total</field>
</ignore>
<ignore>
<field>sales_flat_creditmemo_grid.store_to_order_rate</field>
</ignore>
<ignore>
<field>sales_flat_creditmemo_grid.base_to_order_rate</field>
</ignore>
<ignore>
<field>sales_flat_creditmemo_grid.store_to_base_rate</field>
</ignore>
<ignore>
<field>sales_flat_creditmemo_grid.base_to_global_rate</field>
</ignore>
<ignore>
<field>sales_flat_creditmemo_grid.creditmemo_status</field>
</ignore>
<ignore>
<field>sales_flat_creditmemo_grid.invoice_id</field>
</ignore>
<ignore>
<field>sales_flat_creditmemo_grid.store_currency_code</field>
</ignore>
<ignore>
<field>sales_flat_creditmemo_grid.order_currency_code</field>
</ignore>
<ignore>
<field>sales_flat_creditmemo_grid.base_currency_code</field>
</ignore>
<ignore>
<field>sales_flat_creditmemo_grid.global_currency_code</field>
</ignore>
comment out or remove line inside <destination>
<document_rules>
tag,
<!-- <ignore>
<document>sales_creditmemo_grid</document>
</ignore>
<ignore>
<document>sales_invoice_grid</document>
</ignore>
<ignore>
<document>sales_order_grid</document>
</ignore>
<ignore>
<document>sales_shipment_grid</document>
</ignore>-->
Add below line inside <destination>
part of <field_rules>
tag
<ignore>
<field>sales_order_grid.billing_address</field>
</ignore>
<ignore>
<field>sales_order_grid.shipping_address</field>
</ignore>
<ignore>
<field>sales_order_grid.shipping_information</field>
</ignore>
<ignore>
<field>sales_order_grid.customer_email</field>
</ignore>
<ignore>
<field>sales_order_grid.customer_group</field>
</ignore>
<ignore>
<field>sales_order_grid.subtotal</field>
</ignore>
<ignore>
<field>sales_order_grid.shipping_and_handling</field>
</ignore>
<ignore>
<field>sales_order_grid.customer_name</field>
</ignore>
<ignore>
<field>sales_order_grid.payment_method</field>
</ignore>
<ignore>
<field>sales_order_grid.total_refunded</field>
</ignore>
<ignore>
<field>sales_invoice_grid.store_name</field>
</ignore>
<ignore>
<field>sales_invoice_grid.customer_name</field>
</ignore>
<ignore>
<field>sales_invoice_grid.customer_email</field>
</ignore>
<ignore>
<field>sales_invoice_grid.customer_group_id</field>
</ignore>
<ignore>
<field>sales_invoice_grid.payment_method</field>
</ignore>
<ignore>
<field>sales_invoice_grid.billing_address</field>
</ignore>
<ignore>
<field>sales_invoice_grid.shipping_address</field>
</ignore>
<ignore>
<field>sales_invoice_grid.shipping_information</field>
</ignore>
<ignore>
<field>sales_invoice_grid.subtotal</field>
</ignore>
<ignore>
<field>sales_invoice_grid.shipping_and_handling</field>
</ignore>
<ignore>
<field>sales_shipment_grid.customer_name</field>
</ignore>
<ignore>
<field>sales_shipment_grid.order_status</field>
</ignore>
<ignore>
<field>sales_shipment_grid.billing_address</field>
</ignore>
<ignore>
<field>sales_shipment_grid.shipping_address</field>
</ignore>
<ignore>
<field>sales_shipment_grid.billing_name</field>
</ignore>
<ignore>
<field>sales_shipment_grid.shipping_name</field>
</ignore>
<ignore>
<field>sales_shipment_grid.customer_email</field>
</ignore>
<ignore>
<field>sales_shipment_grid.customer_group_id</field>
</ignore>
<ignore>
<field>sales_shipment_grid.payment_method</field>
</ignore>
<ignore>
<field>sales_shipment_grid.shipping_information</field>
</ignore>
<ignore>
<field>sales_creditmemo_grid.billing_address</field>
</ignore>
<ignore>
<field>sales_creditmemo_grid.shipping_address</field>
</ignore>
<ignore>
<field>sales_creditmemo_grid.customer_group_id</field>
</ignore>
<ignore>
<field>sales_creditmemo_grid.order_status</field>
</ignore>
<ignore>
<field>sales_creditmemo_grid.customer_name</field>
</ignore>
<ignore>
<field>sales_creditmemo_grid.customer_email</field>
</ignore>
<ignore>
<field>sales_creditmemo_grid.payment_method</field>
</ignore>
<ignore>
<field>sales_creditmemo_grid.shipping_information</field>
</ignore>
<ignore>
<field>sales_creditmemo_grid.subtotal</field>
</ignore>
<ignore>
<field>sales_creditmemo_grid.shipping_and_handling</field>
</ignore>
<ignore>
<field>sales_creditmemo_grid.adjustment_positive</field>
</ignore>
<ignore>
<field>sales_creditmemo_grid.adjustment_negative</field>
</ignore>
save map.xml file and
run php magento migrate:data /var/www/html/{{magentoroot}}/vendor/magento/data-migration-tool/etc/ce-to-ce/{{CE version}}/config.xml