SQL Union/select commands

[Fidd1er]

Couple of days ago I barely completed Basic 1, so exuse me if it's a lame question. Here's the deal: I gave up on solving realistic 4 and rushed to youtube, where I found the solution to be very unclear to me. I was told there to inject to following code:
*removed mission spoiler content*
1) Why didn't "SELECT * FROM email" work?
2) Why doesn't UNION work (Why is the ALL required?)
3) wtf is this "null *same*"

Danke =)

EDIT:
In a different subject. Chrome seem to fill all spaces in the link with %20 (or sth), ya have any solution (this really bothers me)? Also, what addons do you use to modify cookies in chrome?

[centip3de]

Couple of days ago I barely completed Basic 1, so exuse me if it's a lame question. Here's the deal: I gave up on solving realistic 4 and rushed to youtube, where I found the solution to be very unclear to me. I was told there to inject to following code:
*removed mission spoiler content*
1) Why didn't "SELECT * FROM email" work?
2) Why doesn't UNION work (Why is the ALL required?)
3) wtf is this "null *same*"

Danke =)

EDIT:
In a different subject. Chrome seem to fill all spaces in the link with %20 (or sth), ya have any solution (this really bothers me)? Also, what addons do you use to modify cookies in chrome?

I, myself, skipped the missions (except the basic, and a few realistic) and came straight to the forums, so I' not sure exactly what you're looking for. However, I do know that there is part of the forum dedicated to just covering the missions, over here. In reply to your edit, though, I've found "Edit This Cookie" does a good job of cookie-managing.

[weekend hacker]

UNION only selects distinct values so to make sure you get everything in the database you'll have to use UNION ALL (although UNION could give some results, the way HTS emulates the exploit could prevent anything but the totally correct answer)

The second query needs to have the exact same number of columns as the first one. This isn't the case, the table you are trying to get has far less columns so you can specify to add additional columns with null in the select part.(null being null values, nothing of value was added but the column count now matches)

In theory you could even add other values then a null value(like the string "boob"), but again you will be limited with how HTS emulates the mission, and whatever value you take will need to have the same datatype as that column in the first table.

I'd suggest you learn more about SQL, you can get the basics on http://www.w3schools.com/sql/default.asp
and even try it out with their demo

[LoGiCaL__]

UNION only selects distinct values so to make sure you get everything in the database you'll have to use UNION ALL (although UNION could give some results, the way HTS emulates the exploit could prevent anything but the totally correct answer)

The second query needs to have the exact same number of columns as the first one. This isn't the case, the table you are trying to get has far less columns so you can specify to add additional columns with null in the select part.(null being null values, nothing of value was added but the column count now matches)

Good explanation. Basically UNION will return distinct records and UNION ALL will return duplicates records (IF ANY) all as one query. Key part being the 2nd paragraph that Weekend wrote.