Sqlte 知识点记录

1、表存在

select count(*) from sqlite_master where type=‘table‘ and name=‘MyTable‘;

sql="CREATE TABLE IF NOT EXISTS MusicList (id integer primary key AutoIncrement,name varchar(20),path varchar(20))";

desc <table> //查看表结构
select * from <table> //查询所有更
select , from table ;//查看指定列
select distinct , from table ;//非重复查询
insert into users(_id,username,password) select * from users;//复制
select username from users where username like ‘S%‘ ;//非重名字首字母为大写S的用户
select username from users where username like ‘__S%‘ ;//非重名字第三个字母为大写S的用户
select * from users where _id in(001,220,230);
select * from user order by _id;//以id的顺序排列
select * from user order by _id desc;//以id反的顺序排

SELECT count(word) AS number FROM cet6_table;

SELECT [word],[explanation] FROM cet6_table ORDER BY word LIMIT 100 OFFSET 200"