数据库语句简单整理
1、创建表
stu 代表表名
sql = "Create table stu(id Integer,sex char,score float )";
Integer 整形
2、插入数据
sql = "insert into stu(sex,score) values('man',98)"; //部分数据插入
sql = "insert into stu values(1,'man',99)"
3、更新数据
sql = "update stu set score = 99 where id = 1";
sql = "update stu set score = 99 ,sex = woman where id = 1";
4、查询数据
sql = "select * from stu"; //全部查询
sql = "select * from stu limit 100"; //查询最后100条数据
sql = "select * from stu where id = 1"; //按条件查询,此处是查询id为1的语句
sql = "select id from stu"; //查询id这一列的数据
5、删除语句
sql = "delete from stu where id = 1"; //删除id为1的这一行
sql = "delete from stu"; //删除整张表数据
6、在表中增加一列
sql = "alter table stu add column address char"; //在表中增加地址这一列
7、删除表
sql = "drop table stu";
8、获取表的行数
QSqlQueryModel *model = new QSqlQueryModel();
model->setQuery(query);
int row = model->rowCount();