我可以确认 psycopg2 已安装(使用 conda install -c anaconda psycopg2
),但似乎 psycopg2 无法导入到我的 python 脚本或解释器无法找到它。我也尝试使用 pip3 安装,满足要求,这意味着 psycopg2 已经安装,但无法理解为什么我的脚本无法导入它。使用 Mac(操作系统 v10.14.4)
$ python create_tables.py
Traceback (most recent call last):
File "create_tables.py", line 1, in <module>
import psycopg2
ModuleNotFoundError: No module named 'psycopg2'
$ pip3 install psycopg2
Requirement already satisfied: psycopg2 in /usr/local/lib/python3.7/site-packages (2.8.2)
$ pip3 install psycopg2-binary
Requirement already satisfied: psycopg2-binary in /usr/local/lib/python3.7/site-packages (2.8.2)
python -V
Python 3.7.0
知道为什么会这样吗?
编辑: create_table.py
import psycopg2
from config import config
def create_tables():
""" create tables in the PostgreSQL database"""
commands = (
"""
CREATE TABLE vendors (
vendor_id SERIAL PRIMARY KEY,
vendor_name VARCHAR(255) NOT NULL
)
""",
""" CREATE TABLE parts (
part_id SERIAL PRIMARY KEY,
part_name VARCHAR(255) NOT NULL
)
""",
"""
CREATE TABLE part_drawings (
part_id INTEGER PRIMARY KEY,
file_extension VARCHAR(5) NOT NULL,
drawing_data BYTEA NOT NULL,
FOREIGN KEY (part_id)
REFERENCES parts (part_id)
ON UPDATE CASCADE ON DELETE CASCADE
)
""",
"""
CREATE TABLE vendor_parts (
vendor_id INTEGER NOT NULL,
part_id INTEGER NOT NULL,
PRIMARY KEY (vendor_id , part_id),
FOREIGN KEY (vendor_id)
REFERENCES vendors (vendor_id)
ON UPDATE CASCADE ON DELETE CASCADE,
FOREIGN KEY (part_id)
REFERENCES parts (part_id)
ON UPDATE CASCADE ON DELETE CASCADE
)
""")
conn = None
try:
# read the connection parameters
params = config()
# connect to the PostgreSQL server
conn = psycopg2.connect(**params)
cur = conn.cursor()
# create table one by one
for command in commands:
cur.execute(command)
# close communication with the PostgreSQL database server
cur.close()
# commit the changes
conn.commit()
except (Exception, psycopg2.DatabaseError) as error:
print(error)
finally:
if conn is not None:
conn.close()
if __name__ == '__main__':
create_tables()
原文由 arilwan 发布,翻译遵循 CC BY-SA 4.0 许可协议
是的,找到了解决方案,
成功了!