从语言 sql postgresql 中的 upsert 过程返回 ID

Question

I have a SQL upsert query and I want to return inserted record ID or updated record ID of the locations table. What changes do I need in the query? (Note: the name column is unique)

CREATE OR REPLACE PROCEDURE locations_upsert
(
    _name        TEXT,
    _address     TEXT,
    _postal_code TEXT,
    _country     TEXT
)
LANGUAGE SQL
AS $$
    INSERT INTO locations
    (
        name,
        address,
        postal_code,
        country
    )
    VALUES
    (
        _name,
        _address,
        _postal_code,
        _country
    )
    ON CONFLICT (name)
    DO UPDATE  
    SET 
        address = _address,
        postal_code = _postal_code,
        country = _country
$$;

Answer 1

Change definition of procedure to function which returns integer value and use

INSERT INTO ... RETURNING id

UPDATE ... RETURNING id

expression.

Answer 2

Change the procedure to a function and declare either int or bigint as return type:

CREATE OR REPLACE FUNCTION locations_upsert(
  _name        TEXT,
  _address     TEXT,
  _postal_code TEXT,
  _country     TEXT
) RETURNS bigint
AS $$ 
  INSERT INTO locations  
    (name, address, postal_code, country) VALUES
    (_name,_address,_postal_code,_country)
   ON CONFLICT (name)
   DO UPDATE SET 
     address = _address,
     postal_code = _postal_code,
     country = _country
   RETURNING id;    
$$ LANGUAGE sql;

Alternatively you can use the table name as return data type - RETURNS locations -, which will enable you to return the whole record - RETURNING * :

CREATE OR REPLACE FUNCTION locations_upsert(
  _name        TEXT,
  _address     TEXT,
  _postal_code TEXT,
  _country     TEXT
) RETURNS locations
AS $$ 
  INSERT INTO locations  
    (name, address, postal_code, country) VALUES
    (_name,_address,_postal_code,_country)
    ON CONFLICT (name)
    DO UPDATE SET 
      address = _address,
      postal_code = _postal_code,
      country = _country
  RETURNING *;  
$$ LANGUAGE sql;

Demo: db<>fiddle