How do I copy data between tables PostgreSQL

postgresql, set, sql, sql-update

Solution

This should work:

UPDATE document_invoice t1 
SET company_name = t2.company_name
FROM account_company t2 
WHERE t1.company_id = t2.company_id

Problem

I have two tables: account_company and document_invoice. Table account_company has 2 columns: company_id and company_name. Table document_invoice has the same columns: company_id and company_name. Something happened and delete all data from column company name from document_invoice. How can I write SQL query to copy data from account company table to document_invoice? I have been using UPDATE and SET but I don't know exactly how. ``` UPDATE document_invoice SET company_name = (SELECT company_name FROM account_company) WHERE document_id.company_name=document_id.account ```

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