如何在MySQL DB中添加当前值

Question

Hi i have a DB Entry that only consists of a number. and i want to Make it where users on my site can Exchange from One to the Other and i know how to do all that but i dont wanna Replace the current value i just wanna add for example 1,000 to it what code can i use in PHP ?

Answer 1

<?php
$con = mysql_connect("localhost","peter","abc123");
if (!$con)
  {
  die('Could not connect: ' . mysql_error());
  }

mysql_select_db("my_db", $con);

mysql_query("UPDATE `some_table` SET `value` = `value` + 1000 WHERE `id` = 1");

mysql_close($con);
?> 

update like this

Answer 2

if you have a value in some table in some database all you have to do is to issue an update statement for that fields.

For example, lets say we have table like this

+--------------+
| some_table   |
+--------------+
| id   | value |
+--------------+
| 1    | 10    |
+--------------+

So your update will be as follows:

UPDATE `some_table` SET `value` = `value` + 1000 WHERE `id` = 1

See more info on how to execute mysql queries with php .