mysql> select SUM(post_thanks_amount) from post where userid=1 and dateline > (UNIX_TIMESTAMP() -3600*24*30);
+-------------------------+
| SUM(post_thanks_amount) |
+-------------------------+
|                     128 |
+-------------------------+
1 row in set (0.01 sec)

mysql> select SUM(post_thanks_amount) from post where userid=302122727 and dateline > (UNIX_TIMESTAMP() -3600*24*30);
+-------------------------+
| SUM(post_thanks_amount) |
+-------------------------+
|                      29 |
+-------------------------+
1 row in set (0.00 sec)

mysql> describe post;
+--------------------+----------------------+------+-----+---------+----------------+
| Field              | Type                 | Null | Key | Default | Extra          |
+--------------------+----------------------+------+-----+---------+----------------+
| postid             | int(10) unsigned     | NO   | PRI | NULL    | auto_increment |
| threadid           | int(10) unsigned     | NO   | MUL | 0       |                |
| username           | varchar(100)         | NO   |     |         |                |
| userid             | int(10) unsigned     | NO   | MUL | 0       |                |
| title              | varchar(250)         | NO   | MUL |         |                |
| dateline           | int(11)              | NO   | MUL | 0       |                |
| pagetext           | mediumtext           | YES  |     | NULL    |                |
| allowsmilie        | smallint(6)          | NO   |     | 0       |                |
| showsignature      | smallint(6)          | NO   |     | 0       |                |
| ipaddress          | varchar(45)          | NO   | MUL | NULL    |                |
| iconid             | smallint(5) unsigned | NO   |     | 0       |                |
| visible            | smallint(6)          | NO   | MUL | 0       |                |
| topic              | int(3)               | NO   |     | 0       |                |
| parentid           | int(10) unsigned     | NO   |     | 0       |                |
| attach             | smallint(5) unsigned | NO   |     | 0       |                |
| infraction         | smallint(5) unsigned | NO   |     | 0       |                |
| reportthreadid     | int(10) unsigned     | NO   |     | 0       |                |
| post_thanks_amount | int(10) unsigned     | NO   |     | 0       |                |
| b8rating           | float                | YES  |     | NULL    |                |
| postkeywords       | varchar(128)         | YES  |     | NULL    |                |
| description        | varchar(256)         | YES  |     | NULL    |                |
| googlebotlastvisit | int(11)              | NO   |     | 0       |                |
| bingbotlastvisit   | int(11)              | NO   |     | 0       |                |
+--------------------+----------------------+------+-----+---------+----------------+
23 rows in set (0.00 sec)