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' )
database name:db_id airline
Air Carriers table Air Carriers Cols: Code dtype integer, Description dtype text, 
Airports table Airports Cols: Code dtype text, Description dtype text, 
Airlines table Airlines Cols: flight date dtype text, operator carrier airline id dtype integer, tail number dtype text, operator carrier flight number dtype integer, origin airport id dtype integer, origin airport sequence id dtype integer, origin city market id dtype integer, ORIGIN dtype text, destination airport id dtype integer, destination airport sequence id dtype integer, destination city market id dtype integer, destination dtype text, scheduled local departure time dtype integer, departure time dtype integer, Departure delay dtype integer, departure delay new dtype integer, arrival time dtype integer, arrival delay dtype integer, arrival delay new dtype integer, CANCELLED dtype integer, cancellation code dtype text, scheduled elapsed time dtype integer, actual elapsed time dtype integer, carrier delay dtype integer, weather delay dtype integer, National Aviavtion System delay dtype integer, security delay dtype integer, late aircraft delay dtype integer, 
