sqlite3.connect('example.db'):创建一个数据库连接,连接到名为’example.db’的数据库文件。 步骤2:执行SQL查询操作 接下来,我们需要执行一个SQL查询操作,使用SELECT语句并加上WHERE条件。以下是示例代码: # 创建一个游标对象cur=conn.cursor()# 执行查询操作cur.execute("SELECT * FROM
# coding:utf-8 import sqlite3 # 创建或连接数据库 conn = sqlite3.connect("test.db") # 删除数据 conn.execute("DELETE FROM user WHERE user_name = 'python'") conn.commit() # 查询数据 cursor = conn.execute("SELECT * FROM user") for row in cursor.fetchall(): print(row) conn.close(...
mysql> select count(*) from hero where h_gender = 1; +---+ | count(*) | +---+ | 5 | +---+ 1. 2. 3. 4. 5. 6. 方法二: mysql> select h_gender as 性别,count(*) from hero group by h_gender having h_gender=1; +---+---+ | 性别 | count(*) | +---+---+ ...
conn = sqlite3.connect('example.db') # 创建游标对象 cursor = conn.cursor() # 执行SELECT语句 cursor.execute("SELECT * FROM table_name WHERE condition") # 获取查询结果 result = cursor.fetchall() # 执行UNION语句 cursor.execute("SELECT * FROM table1 UNION SELECT * FROM table2") #...
打开SQLite数据库命令行窗口使用select命令运行 sqlite>#算数函数,注意SQLite 3命令无法识别#及其后的备注 sqlite>selectabs(-234);#返回绝对值234sqlite>selectmax(1,2,4,5,7);#返回最大值7sqlite>selectmin(1,2,4,5,7);#返回最小值1sqlite>selectrandom(*);#返回随机值-6942185573729877674sqlite>selectround...
import sqlite3 conn=sqlite3.connect('student.db')cursor=conn.cursor()cursor.execute('select * from sqlite_master where type="table" and name="score"')result=cursor.fetchall()print(result)cursor.close()conn.close()运行结果如下：[('table', 'score', 'score', 2, 'CREATE TABLE score (Sn...
SELECT*FROMsqlite_masterWHEREtype='table'; 查询某张表的所有字段 PRAGMAtable_info(表名); 示例: PRAGMAtable_info(sqlite_sequence); 2. python 操作sqlite3,获取sql 查询结果及对应查询结果的列名的方法 classDBOperate(object):""" 数据库操作类
SQL_QUERY_ONE_DATA = "SELECT * FROM PEOPLE WHERE id={}" def query_one(self, id): """ 查询一条数据 :param id: :return: """ self.cursor.execute(SQL_QUERY_ONE_DATA.format(id)) # fetchone():查询第一条数据 # fetchall():查询所有数据 # fetchmany(1):查询固定的数量的数据 result ...
'SQLITE_READ', 'SQLITE_REINDEX', 'SQLITE_SELECT', 'SQLITE_TRANSACTION', 'SQLITE_UPDATE', 'Statement', 'Time', 'TimeFromTicks', 'Timestamp', 'TimestampFromTicks', 'Warning', '__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__...
>>> cur.execute("select * from books where author='first'") <sqlite3.Cursor object at 0x104f297a0> >>> cur.fetchall() [('physics', 'first', 'c')]5.删除 删除也是操作数据库必须的动作: >>> cur.execute("select * from books") <sqlite3.Cursor object at 0x104f297a0> >>> cur...