Question

Hi..i 텍스트와 정수 values..my 코드를 모두 잘 작동 보유하고 내 테이블에서 항목을 검색하려고 sqlite3를 데이터베이스에 ... 그러나 이것은 당신이 원하는

import psycopg2 
class database: 

    def __init__(self): 

     self.con=psycopg2.connect("dbname='book_store' user='postgres' password='5283' host='localhost' port='5432' ") 
     self.cur=self.con.cursor() 
     self.cur.execute("CREATE TABLE if not exists books(id SERIAL PRIMARY KEY,title TEXT NOT NULL UNIQUE,author TEXT NOT NULL,year integer NOT NULL,isbn integer NOT NULL UNIQUE)") 
     self.con.commit() 

    def insert(self,title,author,year,isbn): 
     try: 
     self.cur.execute("INSERT INTO books(title,author,year,isbn) VALUES(%s,%s,%s,%s)",(title,author,year,isbn)) 
     self.con.commit() 
     except: 
      #print("already exists..") 
      pass 

    def view(self): 
     self.cur.execute("SELECT * FROM books") 
     rows=self.cur.fetchall() 
     print(rows) 

    def search(self,title="",author="",year="",isbn=""): 
     self.cur.execute("SELECT * FROM books WHERE title=%s or author=%s or year=%s or isbn=%s",(title,author,year,isbn)) 
     row=self.cur.ferchall() 
     print(row) 

db=database() 
#db.insert("The Naughty","AparnaKumar",1995,234567654) 
db.view() 
db.search(year=1995) 

Answer 1

.. PostgreSQL 데이터베이스에 데이터 오류가 발생합니다 :

def search(self, title=None, author=None, year=None, isbn=None): 
    self.cursor.execute(""" 
     select * 
     from books 
     where 
      (title = %(title)s or %(title)s is null) 
      and 
      (author = %(author)s or %(author)s is null) 
      and 
      (year = %(year)s or %(year)s is null) 
      and 
      (isbn = %(isbn)s or %(isbn)s is null) 
     """, 
     {'title': title, 'author': author, 'year': year, 'isbn': isbn} 
    )