CREATE TABLE table_50434 ("Name" CLOB, "Latitude" CLOB, "Longitude" CLOB, "Diameter" FLOAT, "Year named" FLOAT)

How many years is ur sulcus listed with a diameter less than 1,145.0?
SELECT COUNT("Year named") FROM table_50434 WHERE "Name" = 'ur sulcus' AND "Diameter" < '1,145.0'
SELECT COUNT("Year named") FROM "table_50434" WHERE "Diameter" < '1,145.0' AND "Name" = 'ur sulcus'