我有一个MySQL语句,它打印WeddingDresses从9月到9月的销售额: SUM( preis) AS Price, count(*) as Number WHERE typ = 'BridalGown' ORDERBY Year ASC
当一个BridalGown (在屏幕截图中是Brautkleid )将被出售时,一个新的条目
我有一列'hour‘我有一列'kind’(它可以是1,2或3)SELECT count(id), SUM(hour) as totHour, SUM( IF ( kind =1, 1, 0 ) ) as countKindOneSELECT count(id), SUM(hour) as totHour, COUNT( IF ( kind = 1 ) ) as countKindOne但是mysql告诉我我有一个错误.