使用 psycopg2 从 csv 文件创建 Postgresql table

Question

您好，我正在寻找可以让我从 csv 文件创建 table 的解决方案。我在另一个论坛上找到解决方案。此代码如下所示：

import csv
import psycopg2
import os
import glob


conn = psycopg2.connect("host= localhost port=5433  dbname=testDB user= postgres password= ************")
print("Connecting to Database")

cur = conn.cursor()
csvPath = "W:\Maciej.Olech\structure_files"

# Loop through each CSV
for filename in glob.glob(csvPath+"*.csv"):
# Create a table name
    tablename = filename.replace("W:\Maciej.Olech\structure_files", "").replace(".csv", "")
    print(tablename)

    # Open file
    fileInput = open(filename, "r")

    # Extract first line of file
    firstLine = fileInput.readline().strip()


    # Split columns into an array [...]
    columns = firstLine.split(",")
     

    # Build SQL code to drop table if exists and create table
    sqlQueryCreate = 'DROP TABLE IF EXISTS '+ tablename + ";\n"
    sqlQueryCreate += 'CREATE TABLE'+ tablename + "("

        #some loop or function according to your requiremennt
        # Define columns for table
    for column in columns:
        sqlQueryCreate += column + " VARCHAR(64),\n"

        sqlQueryCreate = sqlQueryCreate[:-2]
        sqlQueryCreate += ");"

cur.execute(sqlQueryCreate)
conn.commit()
cur.close()

我尝试运行此代码，但出现此错误：

C:\Users\MACIEJ~1.OLE\AppData\Local\Temp/ipykernel_5320/1273240169.py in <module>
     40         sqlQueryCreate += ");"
     41 
---> 42 cur.execute(sqlQueryCreate)
     43 conn.commit()
     44 cur.close()

NameError: name 'sqlQueryCreate' is not defined

我不明白为什么会出现此错误，因为定义了 sqlQueryCreate。任何人都知道出了什么问题？感谢您的帮助。

Answer 1

您的代码存在一些问题。

在 Windows 中，路径需要转义 \。
你的cur.execute(sqlQueryCreate)和conn.commit()缩进错了。 sqlQueryCreate = sqlQueryCreate[:-2] 同上和 sqlQueryCreate += ");"
编辑：意识到您的 glob.glob() 参数不正确。你想要的：W:\Jan.Bree\structure_files\*.csv，你实际拥有的W:\Jan.Bree\structure_files*.csv

import csv
import psycopg2
import os
import glob


conn = psycopg2.connect("host= localhost port=5433  dbname=testDB user= postgres password= ************")
print("Connecting to Database")

cur = conn.cursor()
csvPath = "W:\Jan.Bree\structure_files"

# Loop through each CSV
for filename in glob.glob(os.path.join(csvPath,"*.csv")):
# Create a table name
    tablename = filename.replace("W:\Jan.Bree\structure_files", "").replace(".csv", "")
    print(tablename)

    # Open file
    fileInput = open(filename, "r")

    # Extract first line of file
    firstLine = fileInput.readline().strip()

    # Split columns into an array [...]
    columns = firstLine.split(",")

    # Build SQL code to drop table if exists and create table
    sqlQueryCreate = 'DROP TABLE IF EXISTS '+ tablename + ";\n"
    sqlQueryCreate += 'CREATE TABLE'+ tablename + "("

    #some loop or function according to your requiremennt
    # Define columns for table
    for column in columns:
        sqlQueryCreate += column + " VARCHAR(64),\n"

    sqlQueryCreate = sqlQueryCreate[:-2]
    sqlQueryCreate += ");"

    cur.execute(sqlQueryCreate)
    conn.commit()

cur.close()

这应该涵盖问题；但我无法测试代码我不使用 psycopg2。我假设 connect() 有效。

使用 psycopg2 从 csv 文件创建 Postgresql table

Create Postgresql table from csv file using psycopg2

python

csv

postgresql

psycopg2