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python sqlalchemy动态顺序_Python_Sqlite_Sqlalchemy - Fatal编程技术网

python sqlalchemy动态顺序

python sqlalchemy动态顺序,python,sqlite,sqlalchemy,Python,Sqlite,Sqlalchemy,如何基于变量动态设置order by direction,如sqlite db的sqlalchemy查询的asc或desc 伪代码如下: sort_order = "asc" sql_session.query(ResultsDBHistory).order_by(sort_order(ResultsDBHistory.postsize)).limit(max_items_shown) 如果我尝试此操作,它将不接受字符串。您可以访问.asc或.desc方法作为ResultsDBHistory

如何基于变量动态设置order by direction,如sqlite db的sqlalchemy查询的asc或desc

伪代码如下:

sort_order = "asc"

sql_session.query(ResultsDBHistory).order_by(sort_order(ResultsDBHistory.postsize)).limit(max_items_shown)
如果我尝试此操作,它将不接受字符串。

您可以访问.asc或.desc方法作为ResultsDBHistory.postsize上的属性:

as列具有asc和desc方法。

您可以在ResultsDBHistory.postsize上访问.asc或.desc方法作为属性:

as列具有asc和desc方法

order = 'asc'
column_sorted = getattr(ResultsDBHistory.postsize, order)()
sql_session.query(ResultsDBHistory).order_by(column_sorted).limit(max_items_shown)