【问题标题】:limit number of rows peewee retrieve限制peewee检索的行数
【发布时间】:2017-08-04 09:43:40
【问题描述】:

我有以下 python 源文件来从 MySQL 数据库中检索行。问题是在订阅者表中检索的行太多。我怎样才能限制小块行来检索和处理等等?

class subinfo(peewee.Model):
    sub_id = peewee.IntegerField()
    active = peewee.BooleanField()
    sub_type = peewee.IntegerField()
    sub_cat = peewee.TextField()

    class Meta:
        database = locdb

class subscriber(peewee.Model):
    sub_id = peewee.IntegerField(unique=True, primary_key=True)
    sub_start = peewee.DateTimeField()
    sub_end = peewee.DateTimeField()
    ref_id = peewee.BigIntegerField()
    class Meta:
        database = locdb

for row in subscriber.select():
    if(row.sub_start >= peewee.datetime.datetime.now()):
        sub1, created = subinfo.get_or_create(sub_id=row.sub_id, active=True)
        if(created == False & sub1.active == False):
            q = subinfo.update(active=True).where(sub_id=row.sub_id)
            q.execute()
    else:
        subinfo.get_or_create(sub_id=row.sub_id, active=False)

【问题讨论】:

标签: python mysql peewee


【解决方案1】:
for row in subscriber.select()

对前 100 行执行此操作:

 for row in subscriber.select().limit(100)

接下来的 100 行:

 for row in subscriber.select().limit(100).offset(100)

等等

【讨论】:

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