from sql cookbook:Additionally, you will find four pivot tables used in this book; T1, T10, T100, and T500. Because these tables exist only to facilitate pivots, I did not find it necessary to give them clever names. The number following the "T" in each of the pivot tables signifies the number of rows in each table starting from 1. For example, the values for T1 and T10: select id from t1; ID ---------- 1 select id from t10; ID ---------- 1 2 3 4 5 6 7 8 9 10t500存储了1-500个数字。
在书的前言有介绍
----------
1 select id from t10; ID
----------
1
2
3
4
5
6
7
8
9
10t500存储了1-500个数字。