树莓派学习笔记——Python SQLite查询历史温度

# -*- coding: utf-8 -*-
import sqlite3

# 连接数据库
con = sqlite3.connect("cpu.db")
cur = con.cursor()

name = 'RPi.CPU'
# 查询记录总数
cur.execute("select count(*) from temps where name=(?);", (name, ))
total = cur.fetchone()

# 返回元组类型
print type(total)
print type(total[0]) 
print total[0]

# -*- coding: utf-8 -*-
import sqlite3

# 连接数据库
con = sqlite3.connect("cpu.db")
cur = con.cursor()

name = 'RPi.CPU'
# 查询数据库，获得最近一小时的记录
cur.execute('''SELECT * FROM temps
                WHERE name=(?) AND tdatetime > datetime('now', 'localtime', '-1 hours')
                ORDER BY tdatetime ASC;''', (name, ))
# 获得所有结果                
rows = cur.fetchall()

for row in rows:
    print row

# -*- coding: utf-8 -*-
import sqlite3

def dict_factory(cursor, row):
    d = {}
    for idx, col in enumerate(cursor.description):
        d[col[0]] = row[idx]
    return d

# 连接数据库
con = sqlite3.connect("cpu.db")
# 指定工厂方法
con.row_factory = dict_factory
cur = con.cursor()

name = 'RPi.CPU'
# 查询数据库，获得最近一小时的记录
cur.execute('''SELECT * FROM temps
                WHERE name=(?) AND tdatetime > datetime('now', 'localtime', '-1 hours')
                ORDER BY tdatetime ASC;''', (name, ))
               
rows = cur.fetchall()

for row in rows:
    print row