queries involving two tables

now we can formulate a query on two tables by

• joining the tables together into a single table
• applying filter and select to the new table

example

• which company sponsored the winner of the java-cup event?
• query is
  select SPONSOR from
  
  filter EVENT = java-jump from
  filter CAFEMEISTER = NAME from
  join EVENTS and ATHLETES
• before filter, we have
  EVENT CAFEMEISTER HOURS NAME SPONSOR
  
  java-jump ben 10 ben starbucks
• final table (result of query) is
  SPONSOR
  
  starbucks

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