将sqlite查询结果导入到文本文件 下班前接到一个需求,要将sqlite数据库中的某个字段导出保存到一个文本中,数据大概有1000w左右,于是我就写了一个python脚本,来做这个事情。 www.2cto.com 01 #!/usr/xxx/bin/python 02 03 import os,sys 04 import sqlite
将sqlite查询结果导入到文本文件
下班前接到一个需求,要将sqlite数据库中的某个字段导出保存到一个文本中,数据大概有1000w左右,于是我就写了一个python脚本,来做这个事情。
www.2cto.com
01
#!/usr/xxx/bin/python
02
03
import os,sys
04
import sqlite3
05
import logging
06
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sys.path.append('.')
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# logger configure
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logger = logging.getLogger()
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handler = logging.FileHandler('/home/admin/tmp/xxx.txt')
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logger.addHandler(handler)
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logger.setLevel(logging.NOTSET)
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sqlfile_path = '/home/admin/tmp/user.sql'
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def write_to_file(guid):
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total_count = get_total_count(guid)
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page_size = 10000
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offset_num = 0
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op_num = 0
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while op_num
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array_list = get_data([guid,page_size,op_num])
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offset_num = offset_num + 1
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op_num = offset_num * page_size
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for n in array_list:
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logger.info(n)
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def get_total_count(guid):
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conn = sqlite3.connect(sqlfile_path)
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cur = conn.cursor()
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cur.execute('select count(*) from table_name where id = \'' + guid + '\'')
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try:
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count = cur.fetchone()[0]
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except:
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count = 0
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cur.close()
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conn.close()
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return count
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def get_data(item):
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conn = sqlite3.connect(sqlfile_path)
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cur = conn.cursor()
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cur.execute('select name from table_name where id = \'' + item[0] + '\' limit ' + item[1] + ' offset ' + item[2])
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array_list = []
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for r in cur.fetchall():
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array_list.append(r[0])
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cur.close()
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conn.close()
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return array_list
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if '__maiin__' == __name__:
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for guid in ['123456789','987654321']:
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write_to_file(guid)
考虑到数据还是有一点大的,所以就每次查询10000条操作,写完后运行起来,然后我就下班走人了,第二天上班发现这个脚本居然还在跑着,一晚上还没有结束。那叫一个头疼啊。。。 这不是 GC 。
既然这么慢,那我就慢慢等吧,然后开始做其他事情去了,GC来了,兄弟我在测试其他程序的时候,一个不小心,在运行脚本的时候,把python脚本跑出来的文本给删了,连python脚本也一起全删了,当我意识过来的时候,泪流满面啊。。。
就在我沮丧的时候,旁边一同学问了我情况,然后默默的给了我一行代码:
1 sqlite3 user.sql "select name from table_name where id = '123456789'" >> xxx.txt
之后十分钟,数据全导出来了,效率真TM高。

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