what is the importance of temporary tables while working at 3 tiers
def temp-table is how to make a temp table.
As far as importance/significance? Memory is faster than disk or network. Smaller tables brought into memory for repeated processing will process faster. If the temp-table is shared across tiers of computers, it runs even faster. You may notice a slow down if memory is short or there is a lot of distance between the tiers, like while using a WAN (wide area network). Most LAN's are reasonable speed so temp tables can improve performance if populated prior to group use.