Postgres upsert using results from select

问题

I'm trying to upsert with postgres using values from a select. It looks like:

INSERT INTO foo (a, b, c)
SELECT a_, b_, c_
-- hairy sql
ON CONFLICT (...condition...) DO UPDATE
SET "c"=???

On conflict, I want to use one of the values from my select statement, but I can't find the right syntax to alias it. How can I do this with Postgres?

回答1:

Use the excluded keyword:

INSERT INTO foo (a, b, c)
SELECT a_, b_, c_
-- hairy sql
ON CONFLICT (...condition...) DO UPDATE
  SET c = excluded.c;

来源：https://stackoverflow.com/questions/44466232/postgres-upsert-using-results-from-select