In my custom module, I have modified the checkout process a bit and added some custom fields in billing address section following the below tutorial:
Now, these custom fields here are saved in a different table in the form of a key=>value pair, based on order_id in sales_order_custom table created by my module itself.
Further, I want to get these values associated with the sales_order module and display some of these key=>value kind of fields in admin sales order grid.
How how do I join these two tables so that the keys also get converted into columns and I can retrieve them directly as "addColumn" index??
I tried following links, but I think they are somewhat not the right way I am approaching..
1) https://plugin.company/blog/join-eav-attribute-flat-table-collection-magento/ - trying this, I got this error : "Invalid entity_type specified: sales_order_custom"
Thanks in advance..