postgres csv import

data.csv

import.sql

CREATE TABLE IF NOT EXISTS t(
    id serial PRIMARY KEY,
    value text
);
CREATE TEMP TABLE csv AS TABLE t;
INSERT INTO t(id,value) VALUES (1,'value1');

COPY csv FROM :FILE DELIMITER ',' CSV;
--COPY csv FROM :FILE DELIMITER ',' CSV HEADER; --1st line is header

INSERT INTO t(id,value)
SELECT id,value FROM csv
WHERE NOT EXISTS (SELECT id FROM t WHERE id = csv.id);

UPDATE t
SET value = (SELECT csv.value FROM csv WHERE csv.id = t.id )
WHERE EXISTS (SELECT * FROM csv WHERE csv.id = t.id AND csv.value != t.value);

SELECT * FROM t;

psql.sh

#!/usr/bin/env bash

db="tmp_$(openssl rand -hex 6)"
createdb "$db"
psql -v "FILE='$PWD/data.csv'" -f import.sql "$db"
dropdb "$db"