PostgreSQL数据库日常学习笔记4-更新数据

摘要: PostgreSQL数据库日常学习笔记4-更新数据

首先复习创建学生表Students。

---注意表名大小写问题
CREATE TABLE public."Students"(
"StudentID" INTEGER PRIMARY KEY,
"StudentName" TEXT NOT NULL,
"StudentBirthday" DATE,
"StudentAddress" VARCHAR(50),
"StudentSalary" REAL        ---学费
);

先在表内插入2条数据。

INSERT INTO public."Students"("StudentID","StudentName","StudentBirthday","StudentAddress","StudentSalary") VALUES
('1','贾明','1988-08-18','江苏省南京市鼓楼区','200')，
('2','贾宝玉','1988-09-09','江苏省南京市鼓楼区','300'),
('3','甄宝玉','1988-08-08','江苏省南京市鼓楼区','200');

更新StudentID=2行StudentBirthday=1988-9-9数据。

UPDATE public."Students" SET "StudentBirthday"='1988-9-9' WHERE "StudentID"=2;

再次练习插入一次修改多个值。

UPDATE public."Students" SET "StudentBirthday"='1988-8-8',"StudentSalary"=300 WHERE "StudentID"=1;

再次插入3条数据。

INSERT INTO public."Students"("StudentID","StudentName","StudentBirthday","StudentAddress","StudentSalary") VALUES
('4','张大宝','1988-08-18','江苏省无锡市梁溪区','100'),
('5','张小宝'  ,'1988-9-9','江苏省无锡市梁溪区','200'),
('6','王小宝',  '1988-8-8','江苏省无锡市新吴区','100');

批量修改某列数据

---批量修改学费数据
UPDATE "public"."Students" SET "StudentSalary" = "StudentSalary" * 1.5 ;

根据条件修改多列数据

---修改多列数据
UPDATE "public"."Students" SET "StudentSalary" = 300 , "StudentAddress" = '江苏省南京市玄武区' WHERE "StudentSalary" > 300 ;

温馨提示：本文代码和截图数据可能会存在不一致情况，请以代码为准。