创建表 列名 类型,
1...create table Student (id integer , name text, sex text, age integer)
2…create table if not exists Student (id integer , name text default ‘张三‘ , sex text not null, age integer)
删除表 表名
drop table Student
插入
所有列插入 表名 值
insert into Student values (1, ‘张三’, ’男’, 18)
部分列插入
insert into Student (name, sex) values ( ‘lisi‘, ‘nv‘)
主键 (唯一, 不能反复)
create table Student (id integer primary key,name text, age integer, sex text )
查询
全部数据
select * from Student
查询姓名这一列 / 两列
select name from Student
select name, sex from Student
条件查询
select * from Student where age > 10
select * from Student where age > 10 and sex = ‘nv‘
select * from Student where age between 15 and 20
升序/降序
select * from Student order by id sac / desc
仅仅要前 5 条
select * from Student order by id asc limit 5
改动
1列
update Student set age = 18 where sex = ‘男’
多列(勿忘逗号分隔)
update Student set age = 16 , sex = ‘男‘ where age < 19
删除
数据
delete from Student where sex = ‘男‘
所有
delete from Student
使用sqlite
1.打开数据库
2.运行sql,做出数据处理
3.关闭数据库
操作
1.打开数据库
2.创建一个数据操作指针 stmt
3.运行sql 语句
4.处理结果