Question

您好我需要详细说明一个大的csv文件（20M行），为每个逗号分隔字段添加双引号。 csv文件有8个字段以逗号分隔，如下所示：

'2016-03-12','12393659','134',,'35533605',189348,9798,gmail.com;live_com.com
'2016-03-12','12390103','138',,'35438006',5133,1897,google.com
'2016-03-12','45616164','139',,'01318800',10945593,596633,facebook.com;tumblr.com;t.co
'2016-03-12','45673436','38',,'86441702',4350985,150327,serving-sys.com;chartboost.com;admarvel.com;mydas.mobi;adap.tv;cloudfront.net

如前所示，前3个字段位于单引号之间，第4个字段为空白，5个单引号之间，第6个字段仅为逗号分隔。我想得到以下结果（即使空的需要双引号也是第4个字段）：

"2016-03-12","12393659","134","","35533605","189348","9798","gmail.com;live_com.com"
"2016-03-12","12390103","138","","35438006","5133","1897","google.com"
"2016-03-12","45616164","139","","01318800","10945593","596633","facebook.com;tumblr.com;t.co"
"2016-03-12","45673436","38","","86441702","4350985,"150327","serving-sys.com;chartboost.com;admarvel.com;mydas.mobi;adap.tv;cloudfront.net"

我使用sed和awk的混合部分获得结果：

sed -e s/\'//g inpu.csv > output.csv eliminate quotes
awk '{gsub(/[^,]+/,"\"&\"")}1' output.csv > output1.csv add double quotes

但是第4个字段不是双引号，我需要尽可能减少精化时间。无论如何有助于在awk中做更好的表现以及第4场双引号。许多thx的帮助。 M.Tave

Answer 1

试试这个awk单行：

 awk -F, -v OFS="," -v re="^'?|'?$" -v q='"' 
                  '{for(i=1;i<=NF;i++)if($i)gsub(re,q,$i);else $i=q$i q}7' file

这个想法是，使用gsub()向那些非空字段添加双引号。那些空字段，只需在头部和尾部添加"即可。替换正则表达式被定义为脚本外部的awk变量，以避免转义。

它适用于您的输入数据：

kent$  awk -F, -v OFS="," -v re="^'?|'?$" -v q='"' '{for(i=1;i<=NF;i++)if($i)gsub(re,q,$i);else $i=q$i q}7' f
"2016-03-12","12393659","134","","35533605","189348","9798","gmail.com;live_com.com"
"2016-03-12","12390103","138","","35438006","5133","1897","google.com"
"2016-03-12","45616164","139","","01318800","10945593","596633","facebook.com;tumblr.com;t.co"
"2016-03-12","45673436","38","","86441702","4350985","150327","serving-sys.com;chartboost.com;admarvel.com;mydas.mobi;adap.tv;cloudfront.net"

Answer 2

如果您的数据非常简单，没有嵌入式引号或换行符，那么您只需要：

$ awk -F"'?,'?" -v OFS='","' '{$1=$1; gsub(/^.|$/,"\"")} 1' file
"2016-03-12","12393659","134","","35533605","189348","9798","gmail.com;live_com.com"
"2016-03-12","12390103","138","","35438006","5133","1897","google.com"
"2016-03-12","45616164","139","","01318800","10945593","596633","facebook.com;tumblr.com;t.co"
"2016-03-12","45673436","38","","86441702","4350985","150327","serving-sys.com;chartboost.com;admarvel.com;mydas.mobi;adap.tv;cloudfront.net"

使用awk在.CSV逗号分隔文件中添加双引号

2 个答案: