示例如下: CREATE OR REPLACE PROCEDURE P_5_12 AS TYPE dnames_tab IS TABLE OF VARCHAR2(30); dept_names dnames_tab := dnames_tab('Shipping','Sales','Finance','Payroll'); -- 初始化 empty_set dnames_tab; -- 相当于NULL
GBase 8s PL/SQL手册 南大通用数据技术股份有限公司 - 66 -
BEGIN IF dept_names IS NULL THEN DBMS_OUTPUT.PUT_LINE('dept_names is null.'); ELSE DBMS_OUTPUT.PUT_LINE('dept_names is not null.'); END IF;
dept_names := empty_set; -- 赋值NULL. IF dept_names IS NULL THEN DBMS_OUTPUT.PUT_LINE('dept_names is null.'); ELSE DBMS_OUTPUT.PUT_LINE('dept_names is not null.'); END IF;