用 Claude Sonnet 5.5 处理日常编程与文档任务

Claude Sonnet 5.5 输出示例

默认努力程度下的回答，未经编辑。

Explain a database index to a new backend developer in three concise sentences. Include one trade-off.

A database index is a separate data structure (typically a B-tree) that stores the values of one or more columns in sorted order along with pointers to the corresponding rows, so the database can find matching rows without scanning the entire table. Think of it like a book's index: instead of reading every page to find a topic, you look it up and jump straight to the right place. The trade-off is that indexes speed up reads but slow down writes (INSERT, UPDATE, DELETE) and consume extra storage, because every change to the table must also be applied to each relevant index.

2026 年 10 月 1 日：输入 65 token，输出 170 token。结果可能有所不同。