How many flights were there from San Diego International airport to Los Angeles International airport in the August of 2018?
flights from refers to ORIGIN; San Diego International airport refers to Description = 'San Diego, CA: San Diego International'; flights to refers to DEST; Los Angeles International airport refers to Description = 'Los Angeles, CA: Los Angeles International'; in the August of 2018 refers to FL_DATE like '2018/8%';
SELECT COUNT(FL_DATE) FROM Airlines WHERE FL_DATE LIKE '2018/8%' AND ORIGIN = ( SELECT T2.ORIGIN FROM Airports AS T1 INNER JOIN Airlines AS T2 ON T1.Code = T2.ORIGIN WHERE T1.Description = 'San Diego, CA: San Diego International' ) AND DEST = ( SELECT T4.DEST FROM Airports AS T3 INNER JOIN Airlines AS T4 ON T3.Code = T4.DEST WHERE T3.Description = 'Los Angeles, CA: Los Angeles International' )