A Taste of MySql 函数(2)

mysql> select space(6);
+----------+
| space(6) |
+----------+
|          |
+----------+
1 row in set (0.00 sec)

mysql> select repeat('ha!',3);
+-----------------+
| repeat('ha!',3) |
+-----------------+
| ha!ha!ha!       |
+-----------------+
1 row in set (0.00 sec)

mysql> select replace('jinrize','jin','Jin');
+--------------------------------+
| replace('jinrize','jin','Jin') |
+--------------------------------+
| Jinrize                        |
+--------------------------------+

1 row in set (0.00 sec)

 

mysql> select reverse('jinrize');
+--------------------+
| reverse('jinrize') |
+--------------------+
| ezirnij            |
+--------------------+
1 row in set (0.00 sec)

mysql>
mysql> select lcase('JINRIZE');
+------------------+
| lcase('JINRIZE') |
+------------------+
| jinrize          |
+------------------+
1 row in set (0.00 sec)

mysql> select lower('JINRIZE');
+------------------+
| lower('JINRIZE') |
+------------------+
| jinrize          |
+------------------+
1 row in set (0.00 sec)

mysql> select ucase('jinrize');
+------------------+
| ucase('jinrize') |
+------------------+
| JINRIZE          |
+------------------+
1 row in set (0.00 sec)

mysql> select upper('jinrize');
+------------------+
| upper('jinrize') |
+------------------+
| JINRIZE          |
+------------------+

1 row in set (0.00 sec)

 

 mysql> update user
    -> set head_pic =load_file("/tmp/pic.jpg")
    -> where user_name='jinrize';

 mysql> select abs(-3);
+---------+
| abs(-3) |
+---------+
|       3 |
+---------+
1 row in set (0.00 sec)

mysql> select 5 div 2;
+---------+
| 5 div 2 |
+---------+
|       2 |
+---------+
1 row in set (0.00 sec)

 mysql> select 5 mod 2;
+---------+
| 5 mod 2 |
+---------+
|       1 |
+---------+
1 row in set (0.00 sec)

mysql> select 5 % 2;
+-------+
| 5 % 2 |
+-------+
|     1 |
+-------+
1 row in set (0.00 sec

mysql> select floor(1.23);
+-------------+
| floor(1.23) |
+-------------+
|           1 |
+-------------+
1 row in set (0.00 sec)

mysql> select floor(-1.23);
+--------------+
| floor(-1.23) |
+--------------+
|           -2 |
+--------------+
1 row in set (0.00 sec)

 

mysql> select ceiling(-1.23);
+----------------+
| ceiling(-1.23) |
+----------------+
|             -1 |
+----------------+
1 row in set (0.00 sec)

mysql> select round(-1.23);
+--------------+
| round(-1.23) |
+--------------+
|           -1 |
+--------------+
1 row in set (0.00 sec)

mysql> select round(-1.83);
+--------------+
| round(-1.83) |
+--------------+
|           -2 |
+--------------+
1 row in set (0.00 sec)

mysql> select exp(2);
+-----------------+
| exp(2)          |
+-----------------+
| 7.3890560989307 |
+-----------------+
1 row in set (0.00 sec)

mysql> select ln(2);
+------------------+
| ln(2)            |
+------------------+
| 0.69314718055995 |
+------------------+
1 row in set (0.00 sec)

mysql> select log(2);
+------------------+
| log(2)           |
+------------------+
| 0.69314718055995 |
+------------------+
1 row in set (0.00 sec)

 mysql> select pi()+0.00000000000000000000;
+-----------------------------+
| pi()+0.00000000000000000000 |
+-----------------------------+
|      3.14159265358979311600 |
+-----------------------------+
1 row in set (0.00 sec)

转载于:https://www.cnblogs.com/jinrize/archive/2009/10/20/1587139.html