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http://www.cnblogs.com/xiaochaohuashengmi/archive/2011/08/25/2153016.html
mysql int(1) tinyint(1)有什麼區別?
我指定了欄位長度,類型還有意義嗎? Reply:mysql 中int(1)和tinyint(1)中的1隻是指定顯示長度，並不表示儲存長度，只有欄位指定zerofill是有用
如int(3)，如果實際值是2，如果列指定了zerofill，查詢結果就是002，左邊用0來填充。 TINYINT[(M)] [UNSIGNED] [ZEROFILL]
A very small integer. The signed range is -128 to 127. The unsigned range is 0 to 255.
INT[(M)] [UNSIGNED] [ZEROFILL]
A normal-size integer. The signed range is -2147483648 to 2147483647. The unsigned range is 0 to 4294967295.
位元限制基本沒有意義。
mysql> create table testint(id int(1), col2 tinyint(1));
Query OK, 0 rows affected (0.06 sec)
mysql> insert into testint values(256, 257);
Query OK, 1 row affected, 1 warning (0.03 sec)
mysql> select * from testint;
+------+------+
| id | col2 |
+------+------+
| 256 | 127 |
+------+------+
1 row in set (0.02 sec)
mysql> insert into testint values(336, 257);
Query OK, 1 row affected, 1 warning (0.02 sec)
mysql> select * from testint;
+------+------+
| id | col2 |
+------+------+
| 256 | 127 |
| 336 | 127 |
+------+------+
2 rows in set (0.00 sec)
mysql> insert into testint values(336, 255);
Query OK, 1 row affected, 1 warning (0.03 sec)
mysql> select * from testint;
+------+------+
| id | col2 |
+------+------+
| 256 | 127 |
| 336 | 127 |
| 336 | 127 |
+------+------+
3 rows in set (0.00 sec)
mysql>
關注一下上邊的warning提示。。。。
----------------------------mysql 中 真，假 這樣的資料應該用什麼資料類型?reply:tinyint(1)
mysql int(1) 與 tinyint(1) 有什麼區別？
