ap查询为空的情况2.FirstOrInit3.FirstOrCreate4.高级查询1.Struct

当通过结构体进行查询时GORM将会只通过非零值字段查询这意味着如果你的字段值为0‘’false或者其他零值时将不会被用于构建查询条件例如

db.Where(User{Name:

non_existing}).Assign(User{Age:

User{Name:

non_existing}).Assign(User{Age:

SELECT

db.Table(orders).Select(AVG(amount)).Where(state

SELECT

users;db.Table(users).Select(COALESCE(age,?),

42).Rows()

(count)db.Model(User{}).Where(name

jinzhu).Count(count)

(count)db.Table(deleted_users).Count(count)

SELECT

deleted_users;db.Table(deleted_users).Select(count(distinct(name))).Count(count)

SELECT

db.Table(orders).Select(date(created_at)

date,

total).Group(date(created_at)).Rows()

for

db.Table(users).Select(date(created_at)

date,

total).Group(date(created_at)).Scan(rets)rows,

err

db.Table(orders).Select(date(created_at)

date,

total).Group(date(created_at)).Having(sum(amount)

100).Rows()

db.Table(orders).Select(date(created_at)

date,

total).Group(date(created_at)).Having(sum(amount)

100).Scan(results)连接

db.Table(users).Select(users.name,

join

}db.Table(users).Select(users.name,

join

users.id).Where(credit_cards.number

Pluck查询

names)db.Table(deleted_users).Pluck(name,

names)扫描