You would use aCURSOR FOR Loopwhen you want to fetch and process every record in a cursor. TheCURSOR FOR Loopwill terminate when all of the records in the cursor have been fetched. 译:当你每次想通过cursor来对每条记录进行取
cursormycursorisselect*fromcat; begin openmycursor; loop fetchmycursorintov_tablename,v_tabletype; null;--youcanusetablenameandv_tabletype endloop; closemycursor; endStudyCursor; 最近在看代码是,发现其实我们还有一个更方便的方法就是使用for in loop … end loop createorreplaceprocedureStudyFor( r...
FORrecordINcursor_nameLOOPprocess_record_statements;ENDLOOP;Code language:PostgreSQL SQL dialect and PL/pgSQL(pgsql) 1) record Therecordis the name of the index that the cursorFOR LOOPstatement declares implicitly as a%ROWTYPErecord variable of the type of the cursor. ...
CLOSE My_Cursor; --关闭游标 DEALLOCATE My_Cursor; --释放游标GO 2. 利⽤游标循环更新MemberService表中的数据（更新每个⽤户所购买服务的时间）DECLARE@UserId varchar(50)DECLARE My_Cursor CURSOR--定义游标 FOR (SELECT UserId FROM dbo.MemberAccount) --查出需要的集合放到游标中 OPEN My_Cursor...
BEGIN OPEN c_num3; FETCH c_num3 INTO v_num3; WHILE c_num3%FOUND LOOP -- 能找到数据则执行循环内语句 FETCH c_num3 INTO v_num3; END LOOP; CLOSE c_num3; END; -- for DECLARE v_num2 VARCHAR2(100); CURSOR c_num2 IS SELECT NAME FROM test_t WHERE ROWNUM < 600000; BEGIN dbms_...
**while** 条件表达式 loop 循环语句 end loop; 1. 2. 3. 4. 2.3简单应用 计算出1到100的和 **for实现:** for i in 1..100 loop i:=i+1; end loop **While实现:** while i<100 loop i:=i+1; end loop; 1. 2. 3. 4.
Cursor For 是在 Cursor 基础上添加了 FOR 命令的一种操作形式。它可以让我们更方便地遍历结果集合,并对每一条记录执行相同的操作。通常情况下,Cursor For 会搭配 LOOP 命令一起使用,以实现对结果集合的循环处理。 Cursor For 示例 假设我们有一个名为Employee的表,其中包含了员工的信息,如员工编号(EmployeeID)...
DECLARE C1 CURSOR FOR ---SELECT code,salary,city FROM employee WHERE city="Beijing"; OPEN C1; loop_label: LOOP - FETCH C1 INTO code_v,salary_v,city_v; --IF SQLCODE=0 THEN ---SET salary_v=salary_v*1.1; ---UPDATE employee SET salary=salary_v#p# ---WHERE...
OPEN emp_cursor; 使用FOR循环遍历游标中的每一行数据 FOR employee IN emp_cursor LOOP 将当前行的薪水加到总薪水上 total_salary := total_salary + employee.salary; END LOOP; 关闭游标 CLOSE emp_cursor; 输出总薪水 DBMS_OUTPUT.PUT_LINE('Total salary: ' || total_salary); ...
游标通常与FOR循环一起使用。以下是一个示例,展示了如何在PL/SQL中使用游标和FOR循环: DECLARE CURSOR my_cursor IS SELECT column1, column2 FROM my_table; BEGIN FOR my_record IN my_cursor LOOP -- 在此处编写对每一行记录的操作 DBMS_OUTPUT.PUT_LINE('Value of column1: ' || my_record.column1)...