SQL construct sql query from table/columns given Explain Join, left join, full join Explain Union How would you improve sluggish SQL query LINUX Load average vs cpu utilization Create sorted list of log files according to size Oh my, root partition is filling up. Why? Explain hard link, soft link Memory, cpu usage How to read compressed text file without uncompressing NETWORKING few subnet questions E-mail slow - why, what can you find from header MISCELLANEOUS Java will not run on web page - what to look for There were few more, including some very basic windows questions, which I did not bother to memorize.