MYSQL selects the date of a table that does not exist in the second table

I have 2 tables

presence table:

matricule  date_effet
248        2017-01-30
248        2017-01-31
248        2017-02-01
248        2017-02-02

Activities table :

Matricule    date
248        2017-01-31
248        2017-02-01
248        2017-02-02

what i want is to extract the dates that exist on the first one and don't exist in the second one in this case 2017-01-30 knowing that the user will select a range date for exemple in this case maybe date between 2017-01-28 and 2017-02-02

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Try this:

SELECT date_effet FROM presence WHERE date_effet NOT IN(SELECT date FROM activities)

The inner SELECT statement will select all the dates from second table, and then the first select will select all the dates from first table which do not exist in the second table.

Hope it helps!