預編譯一次肉津，可以多次執(zhí)行。用來解決一條SQL語句頻繁執(zhí)行的問題偶洋。

預處理語句：prepare 預處理名字 from ‘sql語句’
執(zhí)行預處理：execute 預處理名字 [using 變量]

例題一：

mysql> prepare stmt from 'select * from stuinfo';   # 創(chuàng)建預處理
Query OK, 0 rows affected (0.00 sec)
Statement prepared

mysql> execute stmt;    # 執(zhí)行預處理
+--------+----------+--------+--------+---------+------------+
| stuNo  | stuName  | stuSex | stuAge | stuSeat | stuAddress |
+--------+----------+--------+--------+---------+------------+
| s25301 | 張秋麗         | 男       |     18 |       1 | 北京           |
| s25302 | 李文才        | 男       |     31 |       3 | 上海          |
| s25303 | 李斯文        | 女      |     22 |       2 | 北京           |
| s25304 | 歐陽俊雄        | 男       |     28 |       4 | 天津           |
| s25305 | 諸葛麗麗         | 女      |     23 |       7 | 河南           |
| s25318 | 爭青小子        | 男       |     26 |       6 | 天津           |
| s25319 | 梅超風        | 女      |     23 |       5 | 河北          |
+--------+----------+--------+--------+---------+------------+
7 rows in set (0.00 sec)

例題二：傳遞參數(shù)

mysql> delimiter // 
mysql> prepare stmt from 'select * from stuinfo where stuno=?' // -- ?是位置占位符
Query OK, 0 rows affected (0.00 sec)
Statement prepared

mysql> set @id='s25301';       -- 變量以@開頭玄窝，通過set給變量賦值
    -> execute stmt using @id //  -- 執(zhí)行預處理悍引，傳遞參數(shù)
Query OK, 0 rows affected (0.00 sec)

+--------+---------+--------+--------+---------+------------+
| stuNo  | stuName | stuSex | stuAge | stuSeat | stuAddress |
+--------+---------+--------+--------+---------+------------+
| s25301 | 張秋麗        | 男       |     18 |       1 | 北京           |
+--------+---------+--------+--------+---------+------------+
1 row in set (0.00 sec)

腳下留心：
1、?是位置占位符
2俩块、變量以@開頭
3浓领、通過set給變量賦值

例題三：傳遞多個參數(shù)

mysql> prepare stmt from 'select * from stuinfo where stusex=? and stuaddress=?'  //
Query OK, 0 rows affected (0.00 sec)
Statement prepared

mysql> set @sex='男';
    -> set @addr='北京';
    -> execute stmt using @sex,@addr //
Query OK, 0 rows affected (0.00 sec)

Query OK, 0 rows affected (0.00 sec)

+--------+---------+--------+--------+---------+------------+
| stuNo  | stuName | stuSex | stuAge | stuSeat | stuAddress |
+--------+---------+--------+--------+---------+------------+
| s25301 | 張秋麗        | 男       |     18 |       1 | 北京           |
+--------+---------+--------+--------+---------+------------+
1 row in set (0.00 sec)