本质上对所有游标类的迭代都是在不断的调用 fetchone 方法,不同的是 SSCursor 对 fetchone 方法的实现不同; 流式游标虽然也有fetchall()方法,调用后的结果与普通游标一样返回所有数据,但是最好别去调用,这样会失去流式游标的优势; 若每条数据读取的间隔超过60s,可能会造成异常,这是因为MySQL的NET_WRITE_TIMEOUT...
drivers = [driver for driver in pyodbc.drivers()]print(drivers) Executing SQL Queries: After establishing a connection, SQL queries can be executed. cursor = conn.cursor()cursor.execute("SELECT * FROM table_name") Fetching Results: Retrieve all results or just one. rows = cursor.fetchall()...
因为 OpenSql 类实现了上下文管理器,现在就可以使用 with 语句了。 # 使用定义好的上下文管理器(Context Manager)withOpenSql('mysql','TB')ascs: sql ='select * from goods;'print(cs.execute(sql),type(cs.execute(sql))) data = cs.fetchall()# 处理数据foritemindata:print(item) 方式3:Python 还...
_time > '"+timediff.strftime('%Y-%m-%d %H:%M:%S')+"' ORDER BY event_time;") rows = cursor.fetchall() #Get column names and print them comma delimited columns = [] for column in cursor.description: columns.append(column[0]) print ', '.join(str(x) ...
email varchar, gender varchar, ip_address varchar, cc varchar, country varchar, birthdate varchar, salary float, title varchar, comments ) """)cursor.execute("COPY userdata FROM 'userdata1.parquet' (HEADER)")print(cursor.execute('select count(*)fromuserdata).fetchall())cursor.close()conn.clo...
fetchone()) # fetch the first row print(mycursor.fetchmany(4)) # fetch the next 2 rows print(mycursor.fetchall()) # fetch all the remaining rows print(mycursor.fetchmany()) # the result set is now empty # we close the cursor and conn both mycursor.close() conn.close() Output:...
$sql="SELECT id FROM signup WHERE email=:email"; $query=$dbh->prepare($sql); $query->bindParam(':email',$email,PDO::PARAM_STR); $query->execute(); $results=$query->fetchAll(PDO::FETCH_OBJ); if($query->rowCount()>0)
sql = 'select * from douban;' cur.execute(sql) rows = cur.fetchall() # 把表中所有字段读取出来 count = [] # 每个分类的数量 category = [] # 分类 for row in rows: count.append(int(row[2])) category.append(row[1]) y_pos = np.arange(len(category)) # 定义y轴坐标数 ...