mysql - 更新用户等级

Question

我尝试在单个查询中更新用户的排名，但它因以下错误而崩溃:

ER_PARSE_ERROR: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'UPDATE users SET rank = @r:= (@r+1) ORDER BY score DESC' at line 1

我的查询有什么问题吗？

SET @r=0;UPDATE users SET rank = @r:= (@r+1) ORDER BY score DESC

我收到来自 this answer 的查询

我正在 node.js mysql library 上执行此查询.

    db.query('SET @r=0;UPDATE users SET rank = @r:= (@r+1) ORDER BY score DESC', function(err){
        if (err){
            console.log(err);
            return;
        }
        console.log("Ranking updated successfully.");
    });

Answer 1

怎么样:

SET @r=0;UPDATE users SET rank = (@r+1) ORDER BY score DESC

我不确定您为什么要再次重新分配变量。