IntegrityError错误

Python插入数据库提交失败，一直走IntegrityError错误，没打印错误信息(一定注意编码规范，记住打印错误信息)，以为插不进去，弄了好久，最后打印了错误信息

(sqlite3.IntegrityError) samples.file_type may not be NULL [SQL: u'INSERT INTO samples (file_size, file_type, md5, crc32, sha1, sha256, sha512, ssdeep) VALUES (?, ?, ?, ?, ?, ?, ?, ?)'] [parameters: (53, None, 'hello', 'crc32', 'sha1', 'sha256', 'sha512', None)]

提示为file_type不能为空，但是我建表的时候file_type设置的是不允许为空，而插入的时候file_type传入为NULL，所以Insert不成功，报错IntegrityError

from sqlalchemy import Column, Integer, String
from sqlalchemy import create_engine
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy import Text, Index
from sqlalchemy.exc import SQLAlchemyError, IntegrityError
from sqlalchemy.orm import sessionmaker

Base = declarative_base()

class Sample(Base):
    """Submitted files details."""
    __tablename__ = "samples"

    id = Column(Integer(), primary_key=True)
    file_size = Column(Integer(), nullable=False)
    file_type = Column(Text(), nullable=False)
    md5 = Column(String(32), nullable=False)
    crc32 = Column(String(8), nullable=False)
    sha1 = Column(String(40), nullable=False)
    sha256 = Column(String(64), nullable=False)
    sha512 = Column(String(128), nullable=False)
    ssdeep = Column(String(255), nullable=True)
    __table_args__ = Index("hash_index", "md5", "crc32", "sha1",
                           "sha256", "sha512", unique=True),

    def __repr__(self):
        return "<Sample('{0}','{1}')>".format(self.id, self.sha256)

    def __init__(self, md5, crc32, sha1, sha256, sha512,
                 file_size, file_type=None, ssdeep=None):
        self.md5 = md5
        self.sha1 = sha1
        self.crc32 = crc32
        self.sha256 = sha256
        self.sha512 = sha512
        self.file_size = file_size
        if file_type:
            self.file_type = file_type
        if ssdeep:
            self.ssdeep = ssdeep

engine = create_engine("sqlite:///cuckoo.db",echo=True)   #返回连接引擎

metadata = Base.metadata
metadata.create_all(engine)  #连接或者创建

#sample_mike = Sample("hello", "crc32", "sha1", "sha256", "sha512", 53, None, None)  #非空数据不能传空

sample_mike = Sample("hello", "crc32", "sha1", "sha256", "sha512", 53, "aa", None)

Session = sessionmaker(bind=engine) session = Session() session.add(sample_mike)  #数据库会话
try: 
　　session.commit() #提交
except IntegrityError as e: 
　　print e
except SQLAlchemyError as e: 
　　print e

　　

最后在网上看到一个比较有用的工具sqlite,查看db数据库

sqlite、db、insert.py下载     http://files.cnblogs.com/files/aliflycoris/db.zip