insert all 用法详解

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0、基础数据

CREATE TABLE student(
  SID   NUMBER(10),
  Sname VARCHAR2(10)
);
INSERT INTO student(SID, sname) VALUES(1, 'a');
INSERT INTO student(SID, sname) VALUES(2, 'b');
INSERT INTO student(SID, sname) VALUES(3, 'c');

1、inerrt 语句

1.1 单行插入

INSERT INTO 表名(字段名1, 字段名n) VALUES(字段值1, 字段值n);

1.2 多行插入

1：数据准备
CREATE TABLE student1 AS SELECT * FROM student;
CREATE TABLE student2 AS SELECT * FROM student;

TRUNCATE TABLE student1;
TRUNCATE TABLE student2;

2：语法操作
INSERT ALL
  WHEN ID <= 2 THEN 
       INTO stu1(ID, xm)    -- 注意，没有 “;” 
  ELSE INTO stu2(ID, xm)
SELECT t.id, t.xm FROM stu t

2、update 语句

2.1 单个更新

1、单个：UPDATE student SET Sname = 'a';      

2.2 多个更新

2、多个：UPDATE student
           SET（Sid，Sname）= (SELECT SID, sname FROM student WHERE SID = '1')
         WHERE Sid = 3