程序員開(kāi)發(fā)人員試題(編輯修改稿)
2025-04-21 06:41 本頁(yè)面
【文章內(nèi)容簡(jiǎn)介】 N張表等值聯(lián)合查詢，至少要寫(xiě)幾個(gè)連接條件？A. NB. N1C. N+1哪三個(gè)查詢沒(méi)有問(wèn)題？A. SELECT *FROM employeeswhere salary (SELECT MIN(salary)FROM employeesGROUP BY department_id)。B. SELECT *FROM employeesWHERE salary = (SELECT AVG(salary)FROM employeesGROUP BY department_id)。C. SELECT distinct department_idFROM employeesWHERE salary ANY (SELECT AVG(salary)FROM employeesGROUP BY department_id)。D. SELECT department_idFROM employeesWHERE salary ALL (SELECT AVG(salary)FROM employeesGROUP BY department_id)。E. SELECT last_nameFROM employeesWHERE salary ANY (SELECT MAX(salary)FROM employeesGROUP BY department_id)。F. SELECT department_idFROM employeesWHERE salary ALL (SELECT AVG(salary)FROM employeesGROUP BY AVG(SALARY))。判斷題：1Insert into table_1(id,name) values(,’test’)。這條SQL會(huì)報(bào)錯(cuò)（ ）1select * from table_1 where create_dt = to_date(‘20100102 12:23:45’,’yyyymmdd hh:mi:ss’)這條SQL沒(méi)有問(wèn)題 ( )1查詢時(shí)使用索引一定能加快查詢速度。（ ）1取表中的前40條記錄，以下SQL沒(méi)有問(wèn)題（ ）select t.*,rownum rn from ( select * from table_1 Where create_dt between sysdate 100 and sysdate order by create_dt desc) t where rownum =401表table_1中的記錄Id name1 aa2 bb3 cc表table_2中的記錄ID name2 cc4 dd5 ff執(zhí)行如下SQL，Select id from table_1UnionSelect id from table_2如果為：ID123245如果正確（ ）1表EMPLOYEES如構(gòu)如下：EMPLOYEE_ID NUMBER Primary KeyFIRST_NAME VARCHAR2(25)LAST_NAME VARCHAR2(25)HIRE_DATE DATESelect first_name+last_name from employees。 查詢會(huì)正常執(zhí)行（ ）1下面SQL沒(méi)有問(wèn)題，可以執(zhí)行（ ）Select city,sum(sal),max(id),min(first_name),cou
環(huán)評(píng)公示相關(guān)推薦
鄂ICP備17016276號(hào)-1