Python将numpy数组插入sqlite3数据库

Python将numpy数组插入sqlite3数据库

您可以使用来注册新的

array

数据类型

sqlite3

：

import sqlite3import numpy as npimport iodef adapt_array(arr):    """    http://stackoverflow.com/a/31312102/190597 (SoulNibbler)    """    out = io.BytesIO()    np.save(out, arr)    out.seek(0)    return sqlite3.Binary(out.read())def convert_array(text):    out = io.BytesIO(text)    out.seek(0)    return np.load(out)# Converts np.array to TEXT when insertingsqlite3.register_adapter(np.ndarray, adapt_array)# Converts TEXT to np.array when selectingsqlite3.register_converter("array", convert_array)x = np.arange(12).reshape(2,6)con = sqlite3.connect(":memory:", detect_types=sqlite3.PARSE_DECLTYPES)cur = con.cursor()cur.execute("create table test (arr array)")

使用此设置，您可以简单地插入NumPy数组，而无需更改语法：

cur.execute("insert into test (arr) values (?)", (x, ))

并直接从sqlite作为NumPy数组检索数组：

cur.execute("select arr from test")data = cur.fetchone()[0]print(data)# [[ 0  1  2  3  4  5]#  [ 6  7  8  9 10 11]]print(type(data))# <type 'numpy.ndarray'>