Python操作SQLite3

连接创建数据库

# connect_sqlite3.py
import sqlite3

DB_Name = 'test.db'
# 连接数据库,如果不存在则会在当前目录创建
conn = sqlite3.connect(DB_Name)
print('连接数据库%s成功' % (DB_Name))

程序执行结果:

连接数据库test.db成功

创建数据库表 

# create_table_sqlite3.py
import sqlite3

DB_Name = 'test.db'
Table_Name = 'STUDENT'
# 连接数据库,如果不存在则会在当前目录创建
conn = sqlite3.connect(DB_Name)
try:
    # 创建游标
    cursor = conn.cursor()
    # 创建STUDENT表的SQL语句,默认编码为UTF-8
    SQL = '''
      CREATE TABLE %s (
        SNO CHAR(10),
        SNAME VARCHAR(20) NOT NULL,
        PRIMARY KEY(SNO)
    )
        ''' % (Table_Name)
    # 创建数据库表
    cursor.execute(SQL)

    # 提交到数据库
    conn.commit()
    print('创建数据库表%s成功' % (Table_Name))
except Exception as e:
    print(e)
    # 回滚
    conn.rollback()
    print('创建数据库表%s失败' % Table_Name)
finally:
    # 关闭数据库
    conn.close()

程序执行结果:

创建数据库表STUDENT成功

增删改查

插入数据

# insertData_sqlite3.py
import sqlite3

DB_Name = 'test.db'
# 连接数据库,如果不存在则会在当前目录创建
conn = sqlite3.connect(DB_Name)
try:
    # 创建游标
    cursor = conn.cursor()
    # 向STUDENT表插入数据的SQL语句
    SQL = '''
          INSERT INTO STUDENT VALUES('2016081111','张三'),('2016081112','李四'),('2016081113','王五');
          '''
    # 插入数据
    cursor.execute(SQL)

    # 提交到数据库
    conn.commit()
    print('插入数据到表STUDENT成功')
except Exception as e:
    print(e)
    # 回滚
    conn.rollback()
    print('插入数据到表STUDENT失败')
finally:
    # 关闭数据库
    conn.close()

程序执行结果为:

插入数据到表STUDENT成功

查询数据

# selectData_sqlite3.py
import sqlite3

DB_Name = 'test.db'
# 连接数据库,如果不存在则会在当前目录创建
conn = sqlite3.connect(DB_Name)
try:
    # 创建游标
    cursor = conn.cursor()
    # 查询数据的SQL语句
    SQL = '''
          SELECT * FROM STUDENT;
          '''
    # 查询数据
    cursor.execute(SQL)

    # 获取一条数据
    one = cursor.fetchone()
    print(one)

    # 获取所有数据
    for row in cursor.fetchall():
        print(row)

except Exception as e:
    print(e)
    print('查询数据失败')
finally:
    # 关闭数据库
    conn.close()

程序执行结果为:

('2016081111', '张三')
('2016081112', '李四')
('2016081113', '王五') 

修改数据

# updateData_sqlite3.py
import sqlite3

DB_Name = 'test.db'
# 连接数据库,如果不存在则会在当前目录创建
conn = sqlite3.connect(DB_Name)
try:
    # 创建游标
    cursor = conn.cursor()
    # 查询数据的SQL语句
    SELECT_SQL = '''
          SELECT * FROM STUDENT;
          '''
    # 修改数据的SQL语句
    UPDATE_SQL = '''
             UPDATE STUDENT SET SNAME='%s' WHERE SNO='%s'
             ''' % ('李华', '2016081111')

    # 修改前
    print('修改前')
    cursor.execute(SELECT_SQL)
    for row in cursor.fetchall():
        print(row)
    # 修改数据
    cursor.execute(UPDATE_SQL)
    # 提交到数据库
    conn.commit()

    # 修改后
    print('修改后')
    cursor.execute(SELECT_SQL)
    for row in cursor.fetchall():
        print(row)
except Exception as e:
    print(e)
    print('修改数据失败')
finally:
    # 关闭数据库
    conn.close()

程序执行结果:

修改前
('2016081111', '张三')
('2016081112', '李四')
('2016081113', '王五')
修改后
('2016081111', '李华')
('2016081112', '李四')
('2016081113', '王五')

删除数据

# deleteData_sqlite3.py
import sqlite3

DB_Name = 'test.db'
# 连接数据库,如果不存在则会在当前目录创建
conn = sqlite3.connect(DB_Name)
try:
    # 创建游标
    cursor = conn.cursor()
    # 查询数据的SQL语句
    SELECT_SQL = '''
          SELECT * FROM STUDENT;
          '''
    # 删除数据的SQL语句
    DELETE_SQL = '''
             DELETE FROM STUDENT WHERE SNO='%s'
             ''' % ('2016081111')

    # 删除前
    print('删除前')
    cursor.execute(SELECT_SQL)
    for row in cursor.fetchall():
        print(row)
    # 删除数据
    cursor.execute(DELETE_SQL)
    # 提交到数据库
    conn.commit()

    # 删除后
    print('删除后')
    cursor.execute(SELECT_SQL)
    for row in cursor.fetchall():
        print(row)
except Exception as e:
    print(e)
    print('删除数据失败')
finally:
    # 关闭数据库
    conn.close()

程序执行结果:

删除前
('2016081111', '李华')
('2016081112', '李四')
('2016081113', '王五')
删除后
('2016081112', '李四')
('2016081113', '王五')

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转载自blog.csdn.net/hhy1107786871/article/details/86540125