python.sqlite3 简单操作

import sqlite3

 

def sqlite_basic():

    # Connect to db

    conn = sqlite3.connect('test.db')

    # create cursor

    c = conn.cursor()

    # Create table

    c.execute('''

              create table if not exists stocks

              (date text, trans text, symbol text,

              qty real, price real)

              '''

             )

    # Insert a row of data

    c.execute('''

              insert into stocks

              values ('2006-01-05','BUY','REHT',100,35.14)

              '''

             )

    # query the table

    rows  = c.execute("select * from stocks")

    # print the table

    for row in rows:

      print(row)

    # delete the row

    c.execute("delete from stocks where symbol=='REHT'")

    # Save (commit) the changes

    conn.commit()

    # Close the connection

    conn.close()

     

def sqlite_adv():

    conn = sqlite3.connect('test2.db')

    c = conn.cursor()

    c.execute('''

              create table if not exists employee

              (id text, name text, age inteage)

              ''')

    # insert many rows

    for t in [('1', 'itech', 10),

              ('2', 'jason', 10),

              ('3', 'jack', 30),

             ]:

        c.execute('insert into employee values (?,?,?)', t)

    # create index

    create_index = 'CREATE INDEX IF NOT EXISTS idx_id ON employee (id);'

    c.execute(create_index)

    # more secure

    t = ('jason',)

    c.execute('select * from employee where name=?', t)

    # fetch query result

    for row in c.fetchall():

      print(row)

    conn.commit()

    conn.close()

     

def sqlite_adv2():

    # memory db

    con = sqlite3.connect(":memory:")

    cur = con.cursor()

    # execute sql

    cur.executescript('''

    create table book(

        title,

        author,

        published

    );

    insert into book(title, author, published)

    values (

        'AAA book',

        'Douglas Adams',

 

    );

    ''')

    rows = cur.execute("select * from book")

    for row in rows:

      print("title:" + row[0])

      print("author:" + row[1])

      print("published:" + str(row[2]))

       

def sqlite_adv3():

    import datetime

 

    # Converting SQLite values to custom Python types

    # Default adapters and converters for datetime and timestamp

    con = sqlite3.connect(":memory:", detect_types=sqlite3.PARSE_DECLTYPES|sqlite3.PARSE_COLNAMES)

    cur = con.cursor()

    cur.execute("create table test(d date, ts timestamp)")

 

    today = datetime.date.today()

    now = datetime.datetime.now()

 

    cur.execute("insert into test(d, ts) values (?, ?)", (today, now))

    cur.execute("select d, ts from test")

    row = cur.fetchone()

    print today, "=>", row[0], type(row[0])

    print now, "=>", row[1], type(row[1])

 

    cur.execute('select current_date as "d [date]", current_timestamp as "ts [timestamp]" from test')

    row = cur.fetchone()

    print "current_date", row[0], type(row[0])

    print "current_timestamp", row[1], type(row[1])