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In this on views you state that condition "classified_ads.posted > '1999-01-01' " will not give the desired results because the column 'posted' is nullable hence this condition will compute to NULL whenever 'posted' column is NULL. Hence the query will never return rows where 'posted' value is NULL. And in order to solve this issue you go onto to create a view with the following query: (select * from classified_ads where posted > '1999-01-01') Wont this view suffer from the same issue? Why will this view contain columns where 'posted' column is NULL. Please explain.