未解析引用tmp_list
时间: 2023-05-13 08:06:10 浏览: 93
这个错误通常是由于编译器找不到某个变量或函数的定义而引起的。可能是因为你忘记了包含某个头文件,或者某个函数或变量的定义在其他文件中没有被正确链接。你可以检查一下你的代码,看看是否有任何拼写错误或语法错误,同时也可以检查一下你的编译选项是否正确。如果还是无法解决问题,你可以尝试使用调试工具来帮助你找到问题所在。
相关问题
tmp_list = [[1]] for i in range(1, 10): l1 = tmp_list[i - 1] new_list = [l1[0]] + [l1[i] + l1[i + 1] for i in range(len(l1) - 1)] + [l1[-1]] tmp_list.append(new_list) print(tmp_list)不用列表推导式
好的,这是一个杨辉三角的生成代码。以下是不使用列表推导式的代码:
```
tmp_list = [[1]]
for i in range(1, 10):
l1 = tmp_list[i - 1]
new_list = [l1[0]]
for j in range(len(l1) - 1):
new_list.append(l1[j] + l1[j + 1])
new_list.append(l1[-1])
tmp_list.append(new_list)
print(tmp_list)
```
这段代码与使用列表推导式的代码功能相同,但是使用了显式的循环来生成新的列表。
tmp_table_size
The `tmp_table_size` is a configuration parameter in MySQL that determines the maximum size of internal temporary tables in memory. When a query requires a temporary table, MySQL will attempt to create it in memory if its size is within the limits specified by `tmp_table_size`. If the table exceeds this size, it will be automatically converted to an on-disk temporary table instead.
By default, the value of `tmp_table_size` is set to the maximum allowed value for your MySQL version. However, it's recommended to adjust this parameter based on your specific workload and available system resources.
If you frequently encounter large temporary tables, you may consider increasing the value of `tmp_table_size` to allow for more in-memory creations. This can potentially improve performance by reducing disk I/O operations. However, bear in mind that increasing this value will consume more memory, so ensure that you have enough available memory to accommodate the larger temporary tables.
You can modify the `tmp_table_size` parameter in the MySQL configuration file (`my.cnf` or `my.ini`). Look for the `[mysqld]` section and add or modify the following line:
```
tmp_table_size = <desired_size>
```
Replace `<desired_size>` with the desired value, specified in bytes (e.g., 64M for 64 megabytes). After making the changes, restart the MySQL server for the new configuration to take effect.
Remember to monitor your server's memory usage and performance after adjusting the `tmp_table_size` parameter to ensure it doesn't cause any adverse effects.