单项选择题 Which of the following describes the objects of a DB2 database and their relationships?（）

单项选择题 Which of the following DB2 objects are publicly referenced names that require no special authority or privilege to use them?（）

单项选择题 Given the following statements: CREATE TABLE tab1 (col1 INT); CREATE TABLE tab2 (col1 INT); CREATE TRIGGER trig1 AFTER UPDATE ON tab1 REFERENCING NEW AS new1 FOR EACH ROW MODE DB2SQL INSERT INTO tab2 VALUES(new1.col1); INSERT INTO tab1 VALUES(2),(3); What is the result of the following query? SELECT count(*) FROM tab2;（）