flask中的日期查询-sqlalchemy在等于时为空，当ge或le时为非空

from flask import Flask
from flask_sqlalchemy import SQLAlchemy
from datetime import datetime

app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'your_database_uri'
db = SQLAlchemy(app)

class MyModel(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    date = db.Column(db.Date)

@app.route('/query')
def query_date():
    # 查询等于指定日期的数据
    result_equal = MyModel.query.filter(MyModel.date == datetime(2022, 1, 1)).all()
    if len(result_equal) == 0:
        # 日期为空
        return "日期为空"
    
    # 查询大于等于指定日期的数据
    result_ge = MyModel.query.filter(MyModel.date >= datetime(2022, 1, 1)).all()
    if len(result_ge) != 0:
        # 日期非空
        return "日期非空"

    # 查询小于等于指定日期的数据
    result_le = MyModel.query.filter(MyModel.date <= datetime(2022, 1, 1)).all()
    if len(result_le) != 0:
        # 日期非空
        return "日期非空"

    return "其他情况"

if __name__ == '__main__':
    app.run()