注册完信息点击“注册”出现一下错误：
sqlalchemy.exc.IntegrityError
IntegrityError: (sqlite3.IntegrityError) UNIQUE constraint failed: user.username [SQL: u'INSERT INTO user (username, email, password, date) VALUES (?, ?, ?, ?)'] [parameters: (u'test', u'[email protected]', '6ffd87ffa2daf5192c0a2b891bf8daf7', '2018-07-06 16:45:34.112000')] (Background on this error at: http://sqlalche.me/e/gkpj)

Traceback (most recent call last)
File "C:\Python27\lib\site-packages\flask\app.py", line 1997, in call
return self.wsgi_app(environ, start_response)
File "C:\Python27\lib\site-packages\flask\app.py", line 1985, in wsgi_app
response = self.handle_exception(e)
File "C:\Python27\lib\site-packages\flask\app.py", line 1540, in handle_exception
reraise(exc_type, exc_value, tb)
File "C:\Python27\lib\site-packages\flask\app.py", line 1982, in wsgi_app
ctx = self.request_context(environ)
ctx.push()
error = None
try:
try:
response = self.full_dispatch_request()
except Exception as e:
error = e
response = self.handle_exception(e)
except:
error = sys.exc_info()[1]
File "C:\Python27\lib\site-packages\flask\app.py", line 1614, in full_dispatch_request
rv = self.handle_user_exception(e)
File "C:\Python27\lib\site-packages\flask\app.py", line 1517, in handle_user_exception
reraise(exc_type, exc_value, tb)
File "C:\Python27\lib\site-packages\flask\app.py", line 1612, in full_dispatch_request
rv = self.dispatch_request()
File "C:\Python27\lib\site-packages\flask\app.py", line 1598, in dispatch_request
return self.view_functionsrule.endpoint
File "C:\Users\maker04\Desktop\fmz_extend_api_demo-master\app.py", line 171, in signup
db.session.commit()
File "C:\Python27\lib\site-packages\sqlalchemy\orm\scoping.py", line 153, in do
return getattr(self.registry(), name)(*args, **kwargs)
File "C:\Python27\lib\site-packages\sqlalchemy\orm\session.py", line 943, in commit
self.transaction.commit()
File "C:\Python27\lib\site-packages\sqlalchemy\orm\session.py", line 467, in commit
self._prepare_impl()
File "C:\Python27\lib\site-packages\sqlalchemy\orm\session.py", line 447, in _prepare_impl
self.session.flush()
File "C:\Python27\lib\site-packages\sqlalchemy\orm\session.py", line 2254, in flush
self._flush(objects)
File "C:\Python27\lib\site-packages\sqlalchemy\orm\session.py", line 2380, in _flush
transaction.rollback(_capture_exception=True)
File "C:\Python27\lib\site-packages\sqlalchemy\util\langhelpers.py", line 66, in exit
compat.reraise(exc_type, exc_value, exc_tb)
File "C:\Python27\lib\site-packages\sqlalchemy\orm\session.py", line 2344, in _flush
flush_context.execute()
File "C:\Python27\lib\site-packages\sqlalchemy\orm\unitofwork.py", line 391, in execute
rec.execute(self)
File "C:\Python27\lib\site-packages\sqlalchemy\orm\unitofwork.py", line 556, in execute
uow
File "C:\Python27\lib\site-packages\sqlalchemy\orm\persistence.py", line 181, in save_obj
mapper, table, insert)
File "C:\Python27\lib\site-packages\sqlalchemy\orm\persistence.py", line 866, in _emit_insert_statements
execute(statement, params)
File "C:\Python27\lib\site-packages\sqlalchemy\engine\base.py", line 948, in execute
return meth(self, multiparams, params)
File "C:\Python27\lib\site-packages\sqlalchemy\sql\elements.py", line 269, in _execute_on_connection
return connection._execute_clauseelement(self, multiparams, params)
File "C:\Python27\lib\site-packages\sqlalchemy\engine\base.py", line 1060, in _execute_clauseelement
compiled_sql, distilled_params
File "C:\Python27\lib\site-packages\sqlalchemy\engine\base.py", line 1200, in _execute_context
context)
File "C:\Python27\lib\site-packages\sqlalchemy\engine\base.py", line 1413, in _handle_dbapi_exception
exc_info
File "C:\Python27\lib\site-packages\sqlalchemy\util\compat.py", line 265, in raise_from_cause
reraise(type(exception), exception, tb=exc_tb, cause=cause)
File "C:\Python27\lib\site-packages\sqlalchemy\engine\base.py", line 1193, in _execute_context
context)
File "C:\Python27\lib\site-packages\sqlalchemy\engine\default.py", line 509, in do_execute
cursor.execute(statement, parameters)
IntegrityError: (sqlite3.IntegrityError) UNIQUE constraint failed: user.username [SQL: u'INSERT INTO user (username, email, password, date) VALUES (?, ?, ?, ?)'] [parameters: (u'test', u'[email protected]', '6ffd87ffa2daf5192c0a2b891bf8daf7', '2018-07-06 16:45:34.112000')] (Background on this error at: http://sqlalche.me/e/gkpj)
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可能是什么原因。
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