Two Mysql methods to reorder self-increasing IDs from 1 _mysql

Recently always to initialize data for this project, make a lot of headaches, and the database ID become more and more, to let the self-increase starting from 1: Then use the following method:

method One: If the previous data is not needed, you can directly empty all the data, and the self-added field recovery from 1 start counting
TRUNCATE TABLE name

method Two:DBCC CHECKIDENT (' table_name ', reseed, new_reseed_value) The current value is set to New_reseed_value. If a row has not been inserted into the table since it was created, the first row inserted after the DBCC checkident is executed uses new_reseed_value as the identity. Otherwise, the next inserted row will use New_reseed_value + 1. If the value of new_reseed_value is less than the maximum value in the identity column, a No. 2627 error message will be generated when the table is referenced later.

Method Two will not empty the existing data, the operation is more flexible, not only can return the value of zero, but also for the deletion of a large number of consecutive rows, reset the value and insert new data, or starting from the new value, of course, can not and existing conflicts.
$sql = "Delete from $table _vote";
mysql_query ($sql, $link);
$sql = "ALTER TABLE $table _vote auto_increment=1";
mysql_query ($sql, $link);

The above is the whole content of this article, hope that these two methods for everyone's learning help.