定义CONSTANT变量
最近更新时间: 2025-02-18 16:02:00
postgres=# CREATE OR REPLACE PROCEDURE p_constant() AS
$$
DECLARE
v_int CONSTANT integer := 1;
BEGIN
RAISE NOTICE 'v_int = %',v_int;
END;
$$
LANGUAGE plpgsql;
CREATE PROCEDURE
postgres=# CALL p_constant();
NOTICE: v_int = 1
CALL
#CONSTANT 不能再次赋值
postgres=# CREATE OR REPLACE PROCEDURE p_constant() AS
$$
DECLARE
v_int CONSTANT integer := 1;
BEGIN
RAISE NOTICE 'v_int = %',v_int;
v_int = 10;
END;
$$
LANGUAGE plpgsql;
ERROR: "v_int" is declared CONSTANT
LINE 7: v_int = 10;
^
postgres=#