Upgrading from 1.8 to 2.4

Having issues with the upgrade from 1.8 to 2.4. I have read the read me, and am going through the steps. When I get to the update the tables part, I run into errors. I copied the 1.8-2.4 tables, and pasted them in to the query and hit go. I get errors and do not know how to make it right?

It might help to know which errors you got.

Pasted this:
CREATE TABLE IF NOT EXISTS `jos_uddeim_attachments` (
`id` int(10) unsigned NOT NULL auto_increment,
`mid` int(1) NOT NULL default '0',
`tempname` TEXT NOT NULL,
`filename` TEXT NOT NULL,
`fileid` varchar(32) NOT NULL,
`size` int(1) NOT NULL default '0',
`datum` int(11) default NULL,
PRIMARY KEY (`id`),
KEY `mid` (`mid`),
KEY `fileid` (`fileid`),
KEY `datum` (`datum`)
) ENGINE=MyISAM;

ALTER TABLE `jos_uddeim` ADD `systemflag` INT( 1 ) NOT NULL DEFAULT '0' ;
ALTER TABLE `jos_uddeim` ADD INDEX ( `systemflag` ) ;
UPDATE `jos_uddeim` SET `systemflag` = 1 WHERE `systemmessage` != '' OR `systemmessage` IS NOT NULL ;
UPDATE `jos_uddeim` SET `systemflag` = 2 WHERE `fromid` = `toid` ;
ALTER TABLE `jos_uddeim` ADD `delayed` INT( 1 ) NOT NULL DEFAULT '0' ;
ALTER TABLE `jos_uddeim` ADD INDEX ( `delayed` ) ;
ALTER TABLE `jos_uddeim_emn` ADD `moderated` INT( 1 ) NOT NULL DEFAULT '0' ;

Got the below error:
Error

SQL query:

CREATE TABLE IF NOT EXISTS `jos_uddeim_attachments` (
`id` int( 10 ) unsigned NOT NULL AUTO_INCREMENT ,
`mid` int( 1 ) NOT NULL default '0',
`tempname` TEXT NOT NULL ,
`filename` TEXT NOT NULL ,
`fileid` varchar( 32 ) NOT NULL ,
`size` int( 1 ) NOT NULL default '0',
`datum` int( 11 ) default NULL ,
PRIMARY KEY ( `id` ) ,
KEY `mid` ( `mid` ) ,
KEY `fileid` ( `fileid` ) ,
KEY `datum` ( `datum` )
) ENGINE = MYISAM ;

MySQL said: Documentation
#1046 - No database selected

#1046 - No database selected

Before you execute the SQL commands select the database you want to modify. In the FAQ you will find a step by step guide.

Ok, sorry about that. I picked the database and now I get this error...

SQL query:

ALTER TABLE `jos_uddeim` ADD `systemflag` INT( 1 ) NOT NULL DEFAULT '0';

MySQL said: Documentation
#1146 - Table 'strother_jml02.jos_uddeim' doesn't exist

Do you use a different prefix? If so change "jos_xxxxx" to "YOURPREFIX_xxxxxx" in all SQL commands.