mysql - 选择值为零时给出错误的结果

create table arts (
    `id` int(11) auto_increment,
    `name` varchar(255),
    `source` varchar(255),
    primary key (`id`)
) engine = innodb, charset utf8mb4 collate utf8mb4_croatian_ci;

insert into arts (name,source) values("lorem","lorem");
insert into arts (name,source) values("lorem","lorem");
insert into arts (name,source) values("lorem","lorem");

select * from arts where name = 0;

结果：3行
为什么会这样？任何字段中都没有0值。

最佳答案

涉及到隐式转换：

select * from arts where name = '0';  => 0 rows (no implicit conversion)
select * from arts where name = 0;    => 3 rows (varchar(255) -> INT)

db<>fiddle demo