如何捕获重复？

我是相对较新的Python，我正在导入Excel到PostgreSQL。 Excel中的地址列有我想要的重复项。 什么是最可行的方法去。

import psycopg2 import xlrd book = xlrd.open_workbook("data.xlsx") sheet = book.sheet_by_name("List") database = psycopg2.connect (database = "Excel", user="SQL", password="PASS", host="YES", port="DB") cursor = database.cursor() delete = """Drop table if exists "Python".list""" print (delete) mydata = cursor.execute(delete) cursor.execute('''CREATE TABLE "Python".list (DCAD_Prop_ID varchar(50), Address varchar(50), Addition varchar(50), Block varchar(50), Lot integer, Project_ID integer );''') print "Table created successfully" query = """INSERT INTO "Python".list (DCAD_Prop_ID, Address,Addition,Block ,Lot,Project_ID) VALUES (%s, %s, %s, %s, %s, %s)""" for r in range(1, sheet.nrows): DCAD_Prop_ID = sheet.cell(r,0).value Address = sheet.cell(r,1).value Addition = sheet.cell(r,2).value Block = sheet.cell(r,3).value Lot = sheet.cell(r,4).value Project_ID = sheet.cell(r,5).value values = (DCAD_Prop_ID, Address,Addition,Block ,Lot,Project_ID) cursor.execute(query, values) cursor.close() database.commit() database.close() print "" print "All Done! Bye, for now." print "" columns = str(sheet.ncols) rows = str(sheet.nrows) print "I just imported Excel into postgreSQL" 

Answer 1

这将返回重复的行：

 select DCAD_Prop_ID, Address,Addition,Block,Lot,Project_ID, count(*) from "Python".list group by 1,2,3,4,5,6 having count(*) > 1 

为了消除Python中的重复，使用set ：

 >>> t = ((1,2),(2,3),(1,2)) >>> set(t) set([(1, 2), (2, 3)])