import sqlite3
conn = sqlite3.connect('/tmp/sqlite.db')
cur = conn.cursor()

create_table_stmt = '''CREATE TABLE IF NOT EXISTS test_table (
 id INTEGER PRIMARY KEY AUTOINCREMENT,
 duration INTEGER,
 event_date TEXT,
 parameter TEXT );'''

create_index = 'CREATE INDEX IF NOT EXISTS idx_id ON test_table (id);'
cur.execute(create_table_stmt)
cur.execute(create_index)
conn.commit()

NULL. The value is a NULL value    
INTEGER. The value is a signed integer, stored in 1, 2, 3, 4, 6, or 8 bytes depending on the magnitude of the value
REAL. The value is a floating point value, stored as an 8-byte IEEE floating point number
TEXT. The value is a text string, stored using the database encoding (UTF-8, UTF-16BE or UTF-16LE)
BLOB. The value is a blob of data, stored exactly as it was input

TEXT as ISO8601 strings ('YYYY-MM-DD HH:MM:SS.SSS').
REAL as Julian day numbers, the number of days since noon in Greenwich on November 24, 4714 B.C. according to the proleptic Gregorian calendar.
INTEGER as Unix Time, the number of seconds since 1970-01-01 00:00:00 UTC.

insert_stmt = 'insert into test_table values (?, ?, ?)'
record = (123, '2011-11-30 12:34:56', 'hello world')
cur.execute( insert_stmt, record )
conn.commit()

SELECT
 id,
 duration,
 event_date,
 parameter
 FROM test_table
WHERE
 DATE(event_date) = DATE('now', '-1 day', 'localtime')
ORDER BY id, event_date

datetime() .......................  產生日期和時間
date()  ........................... 產生日期
time()  ........................... 產生時間
strftime() .......................  對以上三個函數產生的日期和時間進行格式化

YYYY-MM-DD
YYYY-MM-DD HH:MM
YYYY-MM-DD HH:MM:SS
HH:MM
HH:MM:SS
now                                 # 其中now是產生現在的時間。

select datetime('now');
結果：2006-10-17 12:55:54

select datetime('2006-10-17');
結果：2006-10-17 12:00:00

select datetime('2006-10-17 00:20:00', '+1 hour', '-12 minute');
結果：2006-10-17 01:08:00

select date('2006-10-17', '+1 day', '+1 year');
結果：2007-10-18

select datetime('now', 'start of year');
結果：2006-01-01 00:00:00

select datetime('now', 'start of month');
結果：2006-10-01 00:00:00

select datetime('now', 'start of day');
結果：2006-10-17 00:00:00

# 盡管第2個參數加上了10個小時，但是卻被第3個參數 start of day 把時間歸零到00:00:00
# 隨后的第4個參數在00:00:00的基礎上把時間增加了10個小時變成了10:00:00。
select datetime('now', '+10 hour', 'start of day', '+10 hour');
結果：2006-10-17 10:00:00

# 把格林威治時區轉換成本地時區。
select datetime('now', 'localtime');
結果：2006-10-17 21:21:47

select datetime('now', '+8 hour');
結果：2006-10-17 21:24:45

select strftime('%Y/%m/%d %H:%M:%S', 'now', 'localtime');