I search for this question and find two handbook page; but they have some difference so I go on to search but I face always different methods below my handbook page

http://drupal.org/node/120630

http://drupal.org/node/81993

Comments

marcvangend’s picture

Both methods look quite similar. One important difference I noticed, is that node/81993 tells you to check the "Add AUTO_INCREMENT value" box. It can cause problems if you don't do that.

enbilulu’s picture

should I select that "Add AUTO_INCREMENT value" box or leave it untick?

marcvangend’s picture

Yes, select "Add AUTO_INCREMENT value".

john.kenney’s picture

i think the auto-increment thing is to allow you to create multiple copies of the same DB vs. overwriting them when you save a new backup.

instead of doing this, i add this to the File Name Template field: __SERVER_____DB__%Y%m%d%H%M%S

this basically adds an identifier for the server the DB is being saved from (localhost vs. live host) and date/time stamps it.

marcvangend’s picture

No, that's not what the "auto-increment thing" does. An AUTO_INCREMENT column in a database is automatically populated when a new row is added. It's value is always one more than the previous row. When you check "add AUTO_INCREMENT value", the value created by this AUTO_INCREMENT behavior is also exported. If you don't, the AUTO_INCREMENT values will be generated by the database while importing.

If don't add the AUTO_INCREMENT value to a Drupal database export, you will encounter problems. For instance, the user table has an AUTO_INCREMENT on the UserID column. AUTO_INCREMENT starts counting from value 1, but the user table starts with UserID 0. If you don't add the AUTO_INCREMENT value to your export, MySQL will try to import the data of user 0 (the anonymous user) as user 1 (the Drupal root user).

enbilulu’s picture

node/120630

I think I should check auto increment

but what about others in node/120630?