To enter the matches of a football championship, the following tables have been defined:
The weather int primary key id, name char (20), int points, NroVitorias, objectives, int goals) Thu ( idTime1 int, idTime2 int, golsTime1 int, golsTime2, primary key (idTime1, idTime2))
Table The weather is preloaded with the data
name of all teams participating in the championship and with all
Zero values remaining. Table The is empty.
Write the SQL commands to resolve the following queries:
idTme2 must be defined as a foreign key referencing the table The weather.
Write the commands to set these 2 foreign keys so that a team that already has a saved game can not be deleted and that if a team's ID is changed, its games are preserved.
Is it possible for me to create a foreign key from a column of one table (Time), by referencing two columns from another table (games)?