sqlite语句
//创建表
create table if not exists yourTableName("
@"id integer primary key autoincrement,"
@"userId integer not null,"
@"purchaseId integer not null,"
@"title text,"
@"dateId datetime default (datetime('now', 'localtime'))"
@")
//删除整张表内容
delete from yourTableName
//使用%@,%ld占位
delete from yourTableName where purchaseId = %ld and userId = %ld
//插入数据
insert into yourTableName (userId, purchaseId, title, dateId) values (%ld, %ld, %@, %@)
//更新数据
update yourTableName set dateId = datetime('now', 'localtime') where purchaseId = %ld and userId = %ld
//据用户ID查询整张表有多少条数据
select count(*) from yourTableName where userId = 416673
//根据一些约束条件查询数据库
select * from yourTableName where userId in (%d, 0) and createUserId != %d order by updateTime desc limit %d offset %d
//查询是否已存在某条记录
select count(*) from yourTableName where purchaseID = 101 and userID = 416673
//给已存在表添加列
alter table yourTableName add createUserId integer default 0