Use EF link postgreSQL, insert data found that need to return Id
But after setting the trigger, the main table increased two data

 CREATE OR REPLACE the FUNCTION "dbo". "measurement_insert_trigger () 
"RETURNS "pg_catalog". "trigger" AS $BODY $
DECLARE 
Id is an integer; 
The BEGIN 
IF (NEW. "ReceivedTimestamp" & gt;=the DATE '2020-01-01' AND 
NEW. "ReceivedTimestamp" & lt; THEN the DATE '2020-06-30') 
INSERT INTO dbo. Orders_202001 VALUES (NEW. *); 
ELSIF (NEW. "ReceivedTimestamp" & gt;=the DATE '2020-07-01' AND 
NEW. "ReceivedTimestamp" & lt; THEN the DATE '2020-12-31') 
INSERT INTO dbo. Orders_202002 VALUES (NEW. *); 
The ELSE 
RAISE the EXCEPTION 'Date out of range. Fix the measurement_insert_trigger () function. '; 
END IF; 
The RETURN of NEW; 
END; 
$BODY $
LANGUAGE PLPGSQL VOLATILE 
COST 100 


CREATE the TRIGGER insert_measurement_trigger 
BEFORE the INSERT ON dbo. "Orders" 
FOR EACH ROW EXECUTE PROCEDURE dbo. Measurement_insert_trigger (); 

The above is the trigger