需要在python中比较1.5GB左右的超大文件

Question

"DF","[e-mail]","FLTINT1000130394756","26JUL2010","B2C","6799.2"
"Rail","[e-mail]","NR251764697478","24JUN2011","B2C","2025"
"DF","[e-mail]","NF2513521438550","01JAN2013","B2C","6792"
"Bus","[e-mail]","NU27012932319739","26JAN2013","B2C","800"
"Rail","[e-mail]","NR251764697526","24JUN2011","B2C","595"
"Rail","[e-mail]","NR251277005737","29OCT2011","B2C","957"
"Rail","[e-mail]","NR251297862893","21NOV2011","B2C","212"
"DF","[e-mail]","NF251327485543","26JUN2011","B2C","17080"
"Rail","[e-mail]","NR2512012069809","25OCT2012","B2C","5731"
"DF","[e-mail]","NF251355775967","10MAY2011","B2C","2000"
"DF","[e-mail]","NF251352240086","22DEC2010","B2C","4006"
"DF","[e-mail]","NF251742087846","12DEC2010","B2C","1000"
"DF","[e-mail]","NF252022031180","09DEC2010","B2C","3439"
"Rail","[e-mail]","NR2151120122283","25JAN2013","B2C","136"
"Rail","[e-mail]","NR2151213260036","28NOV2012","B2C","41"
"Rail","[e-mail]","NR2151313264432","29NOV2012","B2C","96"
"Rail","[e-mail]","NR2151413266728","29NOV2012","B2C","96"
"Rail","[e-mail]","NR2512912359037","08DEC2012","B2C","96"
"Rail","[e-mail]","NR2517612385569","12DEC2012","B2C","96"

以上是示例数据。数据是根据电子邮件地址排序的，文件很大，约为1.5Gb

我想要在另一个csv文件中输出类似这样的内容

"DF","[e-mail]","FLTINT1000130394756","26JUL2010","B2C","6799.2",1,0 days
"Rail","[e-mail]","NR251764697478","24JUN2011","B2C","2025",1,0 days
"DF","[e-mail]","NF2513521438550","01JAN2013","B2C","6792",1,0 days
"Bus","[e-mail]","NU27012932319739","26JAN2013","B2C","800",1,0 days
"Rail","[e-mail]","NR251764697526","24JUN2011","B2C","595",1,0 days
"Rail","[e-mail]","NR251277005737","29OCT2011","B2C","957",1,0 days
"Rail","[e-mail]","NR251297862893","21NOV2011","B2C","212",1,0 days
"DF","[e-mail]","NF251327485543","26JUN2011","B2C","17080",1,0 days
"Rail","[e-mail]","NR2512012069809","25OCT2012","B2C","5731",1,0 days
"DF","[e-mail]","NF251355775967","10MAY2011","B2C","2000",1,0 days
"DF","[e-mail]","NF251352240086","09DEC2010","B2C","4006",1,0 days
"DF","[e-mail]","NF251742087846","12DEC2010","B2C","1000",2,3 days
"DF","[e-mail]","NF252022031180","22DEC2010","B2C","3439",3,10 days
"Rail","[e-mail]","NR2151213260036","28NOV2012","B2C","41",1,0 days
"Rail","[e-mail]","NR2151313264432","29NOV2012","B2C","96",2,1 days
"Rail","[e-mail]","NR2151413266728","29NOV2012","B2C","96",3,0 days
"Rail","[e-mail]","NR2512912359037","08DEC2012","B2C","96",4,9 days
"Rail","[e-mail]","NR2512912359037","08DEC2012","B2C","96",5,0 days
"Rail","[e-mail]","NR2517612385569","12DEC2012","B2C","96",6,4 days
"Rail","[e-mail]","NR2517612385569","12DEC2012","B2C","96",7,0 days
"Rail","[e-mail]","NR2151120122283","25JAN2013","B2C","136",8,44 days
"Rail","[e-mail]","NR2151120122283","25JAN2013","B2C","136",9,0 days

即，如果条目是第一次发生，我需要附加1，如果条目是第二次，我需要附加2，同样地，我的意思是我需要不计算文件中电子邮件地址的出现次数，并且如果电子邮件存在两次或更多次，我想区别在日期之间，记住
日期没有排序，
因此我们还必须针对特定的电子邮件地址对它们进行排序，我正在寻找使用numpy或pandas库或任何其他可以处理这种类型的巨大数据而又不给与错的库的python解决方案绑定内存异常我有带centos
6.3的双核处理器，内存为4GB

Answer 1

另一种可能的方式（系统管理员），避免数据库和SQL查询以及运行时进程和硬件资源中的大量要求。

更新20/04 添加了更多代码和简化方法：

1. 转换的时间戳，以秒（大纪元）和使用UNIX sort，使用电子邮件和这个新的领域（即：sort -k2 -k4 -n -t, < converted_input_file > output_file）
2. 初始化3个变量EMAIL，PREV_TIME和COUNT
3. 在每一行进行交互，如果遇到新的电子邮件，则添加“ 1,0天”。更新PREV_TIME=timestamp，COUNT=1，EMAIL=new_email
4. 下一行：3种可能的情况
   • a）如果同一封电子邮件，不同的时间戳记：计算天数，增加COUNT = 1，更新PREV_TIME，添加“ Count，Difference_in_days”
   • b）如果相同的电子邮件，相同的时间戳：增加COUNT，则添加“ COUNT，0天”
   • c）如果是新电子邮件，请从3开始。

替代1.的是添加一个新字段TIMESTAMP，并在打印出该行后将其删除。

注意：如果1.5GB太大而无法一次整理，请使用电子邮件将其拆分为较小的卡盘。您可以在不同的机器上并行运行这些块

/usr/bin/gawk -F'","' ' { 
    split("JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC", month, " "); 
    for (i=1; i<=12; i++) mdigit[month[i]]=i; 
    print $0 "," mktime(substr($4,6,4) " " mdigit[substr($4,3,3)] " " substr($4,1,2) " 00 00 00"
)}' < input.txt |  /usr/bin/sort -k2 -k7 -n -t, > output_file.txt

output_file.txt：

“ DF”，“ [e-mail]”，“ FLTINT1000130394756”，“ 26JUL2010”，“ B2C”，“
6799.2”，1280102400“ DF”，“ [e-mail]”，“ NF252022031180”，“
09DEC2010”，“ B2C“，” 3439“，1291852800” DF“，” [e-mail]“，”
NF251742087846“，” 12DEC2010“，” B2C“，” 1000“，1292112000” DF“，”
[e-mail]“，” NF251352240086”，“ 22DEC2010”，“ B2C”，“
4006”，1292976000
…

您将输出通过管道传输到Perl，Python或AWK脚本以处理步骤2至4。