Sql 从代码块创建函数
如何将此代码转换为具有相同输出的函数Sql 从代码块创建函数,sql,oracle,function,plsql,Sql,Oracle,Function,Plsql,如何将此代码转换为具有相同输出的函数 declare record_name employees%ROWTYPE; begin FOR record_name IN (SELECT (a.first_name || ' ' || a.last_name) complete_name, b.DEPARTMENT_NAME complete_name2 FROM employees a , departm
declare
record_name employees%ROWTYPE;
begin
FOR record_name IN (SELECT (a.first_name || ' ' || a.last_name) complete_name,
b.DEPARTMENT_NAME complete_name2
FROM employees a , departments b
WHERE ROWNUM < 1000 and a.DEPARTMENT_ID=b.DEPARTMENT_ID)
LOOP
DBMS_OUTPUT.PUT_LINE('Employee name: ' || record_name.complete_name
||'DEPARTMENT name: '||record_name.complete_name2);
END LOOP;
END;
举个简单的例子,我不知道是否有某种类型没有完整性限制,因为不总是varchar4000-enough。但是我听说了一些关于这种类型的东西,但现在我不知道它是否存在
当你们使用这个应用层时,你们必须以某种方式格式化返回的字符串
CREATE TYPE some_employees_record IS RECORD
(emp_name VARCHAR2(4000)
,dept_name VARCHAR2(4000));
CREATE TYPE employees_tab_type IS TABLE OF some_employees_record;
CREATE OR REPLACE
FUNCTION some_employees
RETURN employees_tab_type
PIPELINED
IS
rec some_employees_record;
BEGIN
FOR record_name IN (SELECT (a.first_name || ' ' || a.last_name) complete_name,
b.DEPARTMENT_NAME complete_name2
FROM employees a , departments b
WHERE ROWNUM < 1000 and a.DEPARTMENT_ID=b.DEPARTMENT_ID)
LOOP
rec.emp_name := record_name.complete_name;
rec.dept_name := record_name.complete_name2;
PIPE ROW (rec);
END LOOP;
RETURN;
END;
或在PL/SQL中:
DECLARE
rt employees_tab_type;
BEGIN
rt := some_employees;
FOR i IN 1..rt.COUNT LOOP
DBMS_OUTPUT.put_line(rt(i).emp_name || ', ' || rt(i).dept_name);
END LOOP;
END;
OT:如果记录数超过999,您是否意识到查询将返回一组有效的随机不确定的999条记录
顺便说一句,这只是出于示例目的。如果您唯一的需求是让函数运行查询,我不会这样做。我会返回一个ref游标,或者更好地将查询放在视图中。从Oracle 10g开始,最大varchar为4000。还有,你不认为“+”号赢了吗;连接不起作用?[out_stmt:=out_stmt+“Employee name:”]-应该是| |可能还需要一个异常处理程序,以防溢出out_stmt变量。您是只想打印还是希望函数返回记录集以供进一步操作?对于前者,使用@Sajmon给出的答案,用Put_行替换累积连接。对于后者,您需要创建一个表值函数。
SELECT * FROM TABLE(some_employees);
DECLARE
rt employees_tab_type;
BEGIN
rt := some_employees;
FOR i IN 1..rt.COUNT LOOP
DBMS_OUTPUT.put_line(rt(i).emp_name || ', ' || rt(i).dept_name);
END LOOP;
END;