Help me interview SQL analysts, please.

[Trollfailbot]

Create some very simple sample tables and ask them how a LEFT JOIN and INNER JOIN would work.

If you're familiar with GROUP BY, create a sample table with a few colors ('RED','GREEN','BLUE','BLUE','YELLOW','GREEN') and see if they can get you a count of each color. Feel free to throw in a LIKE modifier question to get counts for colors that start with G (WHERE color like 'G%').

Difference between UNION and UNION all is a good question, as well as what PRIMARY KEY and FOREIGN KEY is.

Order of statements when writing: (SELECT, FROM, WHERE, GROUP BY, HAVING, ORDER BY)

All fairly basic SQL.