CREATE TABLE table_4223 ("Quartier" TEXT, "% 0-19 years" TEXT, "% 20-39 years" TEXT, "% 40-59 years" TEXT, "% 60-74 years" TEXT, "% 75 years and +" TEXT)

How many o-19% are where the quartier is in saint-loup?
SELECT "% 0-19 years" FROM table_4223 WHERE "Quartier" = 'Saint-Loup'
SELECT "% 0-19 years" FROM "table_4223" WHERE "Quartier" = 'Saint-Loup'