選擇底部 n 條記錄的 MySQL 查詢
我們首先建立一個表格 -
mysql> create table DemoTable724 (Value int); Query OK, 0 rows affected (0.79 sec)
使用 insert 命令在表格中插入一些記錄 -
mysql> insert into DemoTable724 values(101); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable724 values(183); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable724 values(983); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable724 values(234); Query OK, 1 row affected (0.21 sec) mysql> insert into DemoTable724 values(755); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable724 values(435); Query OK, 1 row affected (0.28 sec) mysql> insert into DemoTable724 values(675); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable724 values(345); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable724 values(948); Query OK, 1 row affected (0.14 sec)
使用 select 語句顯示錶格中的所有記錄 -
mysql> select *from DemoTable724;
這將產生以下輸出 -
+-------+ | Value | +-------+ | 101 | | 183 | | 983 | | 234 | | 755 | | 435 | | 675 | | 345 | | 948 | +-------+ 9 rows in set (0.00 sec)
以下是選擇底部 n 條記錄的查詢。此處,我們在按 DESC 排序後選擇了 4 條記錄。這將為我們從初始值中提取最後 4 條記錄 -
mysql> select *from DemoTable724 order by Value DESC LIMIT 0,4;
這將產生以下輸出 -
+-------+ | Value | +-------+ | 983 | | 948 | | 755 | | 675 | +-------+ 4 rows in set (0.00 sec)
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