CREATE TABLE table_203_279 (id DECIMAL, "interferometer and observing mode" TEXT, "waveband" TEXT, "limiting magnitude" DECIMAL, "minimum baseline  ( m ) \ ( un-projected ) " DECIMAL, "maximum baseline  ( m ) " DECIMAL, "approx. no. visibility measurements per year\ ( measurements per night x nights used per year ) " DECIMAL, "max ratio of no. phase / no. amplitude measurements\ ( measure of imaging performance ,  0 = none ) " DECIMAL, "accuracy of amplitude2 measurements" TEXT, "accuracy of phase measurements\ ( milli-radians ) " DECIMAL, "number of spectral channels\ ( max in use simultaneously ) " TEXT, "comments" TEXT)

what 's the total limiting matitude of coast visible and coast infrared ?
SELECT SUM("limiting magnitude") FROM table_203_279 WHERE "interferometer and observing mode" IN ('coast visible', 'coast infrared')
SELECT SUM("limiting magnitude") FROM "table_203_279" WHERE "interferometer and observing mode" IN ('coast visible', 'coast infrared')