Note the following points describing various utilities in Oracle Database 11g： 1. It enables the transfer of data from one database to another. 2. It provides a complete solution for the backup， restoration， and recovery needs of the entire database. 3. It enables the loading of data from an external file into tables of an Oracle database. 4. It provides a tape backup management for the Oracle ecosystem. Which point describes the Oracle Data Pump utility（） 1。 2。 3。 4。 1 and 3。 1， 2， 3， and 4。
A user named Arren is executing this query： select table_name，operation，undo_sql from flashback_transaction_query t， （select versions_xid as xid from employees versions between scn minvalue and maxvalue where employee_id = 123） e where t.xid = e.xid； When the query runs，he receives an ORA-01031： insufficient privileges error. Since the user owns the employees table，you know that it is not the problem. Which of the following SQL statements will correct this problem？（） GRANT SELECT ANY TRANSACTION TO ARREN。 GRANT SELECT ON FLASHBACK_TRANSACTION_QUERY TO ARREN。 GRANT SELECT_ANY_TRANSACTION TO ARREN。 GRANT FLASHBACK TO ARREN。 GRANT SELECT ANY VIEW TO ARREN。
垫圈一般置于螺母与（）之间，用以增大两者之间的接触面积。 光孔。 阶梯孔。 被连接件。 连接件。
血小板a颗粒释放的特异蛋白质是（） ADP，ATP。 5-羟色胺和钙离子。 血小板第4因子（PH）和β血小板球蛋白（β-TG）。 血小板促生长因子（PDGF.和凝血酶致敏蛋白（TSP）。
Given: If class Donkey is invoked twice, the first time without assertions enabled, and the second time with assertions enabled, what are the results?（） no output。 no output assert is on。 assert is on。 no output An AssertionError is thrown.。 assert is on An AssertionError is throw。
混凝土结构失稳的加固方法有（）
