如何使用随机值更新MySQL列？

要更新列的随机值，您可以使用以下语法−

update yourTableName set yourColumnName =round(1+rand()*100);

上述语法将生成1到100之间的值。让我们看一个例子并创建一个表−

mysql> create table DemoTable
   (
   Number int
   );
Query OK, 0 rows affected (0.46 sec)

使用insert命令将记录插入表中−

mysql> insert into DemoTable values(10);
Query OK, 1 row affected (0.17 sec)
mysql> insert into DemoTable values(100);
Query OK, 1 row affected (0.11 sec)
mysql> insert into DemoTable values(80);
Query OK, 1 row affected (0.20 sec)
mysql> insert into DemoTable values(100000);
Query OK, 1 row affected (0.39 sec)
mysql> insert into DemoTable values(987);
Query OK, 1 row affected (0.16 sec)

使用select语句显示表中的所有记录−

mysql> select *from DemoTable;

这将产生以下输出−

+--------+
| Number |
+--------+
| 10     |
| 100    |
| 80     |
| 100000 |
| 987    |
+--------+
5 rows in set (0.00 sec)

以下是使用随机值更新列的查询−

mysql> update DemoTable set Number=round(1+rand()*100);
Query OK, 5 rows affected (0.46 sec)
Rows matched: 5 Changed: 5 Warnings: 0

让我们再次显示表记录−

mysql> select *from DemoTable;

这将产生以下输出−

+--------+
| Number |
+--------+
| 33     |
| 88     |
| 41     |
| 39     |
| 70     |
+--------+
5 rows in set (0.00 sec)

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