Python database on-demand query operation
Python queries the SQL server using the fetchone () method to obtain a single piece of data, and the fetchall () method to obtain multiple pieces of data.
fetchone (): This method gets the next query result set. The result set is an object
fetchall (): Receive all returned result rows
rowcount: This is a read-only attribute and returns the number of rows affected by the execute () method
fetchone()：
Return a single tuple, that is, a row (row), if there is no result, return none
fetchall():
Return multiple tuples, that is, return multiple records (rows), if there is no result, return []
Need to indicate: null in sql server and none in Python
The usage is as follows:
pymssql #Load sql server module connect = pymssql.connect() cursor = connect.cursor() id = () sql = %(id) cursor.execute(sql) f1 = cursor.fetchone () sql1 = cursor.execute(sql1) f2 = cursor.fetchall() connect.commit() cursor.close() connect.close() f1: (F1 []) : () (f2)