使用 awk 在 .CSV 逗号分隔文件中添加双引号答案

【问题标题】：Add double quotes in .CSV comma delimited file using awk使用 awk 在 .CSV 逗号分隔文件中添加双引号
【发布时间】：2016-07-03 16:05:11
【问题描述】：

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

'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

如您所见，前 3 个字段在单引号之间，第 4 个为空白，第 5 个在单引号之间，第 6 到第 8 个仅以逗号分隔。我想得到以下结果（也是第 4 个字段，即使为空也需要双引号）：

"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"

我通过 sed 和 awk 混合获得部分结果：

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

但是第四个字段没有双引号，我需要尽可能减少阐述时间。无论如何，有助于以更好的表现和第四场双引号来完成所有工作。非常感谢您的帮助。 M.Tave

【问题讨论】：

标签： csv awk quotes comma

【解决方案1】：

如果您的数据真的那么简单，没有嵌入引号或换行符或任何东西，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"

【讨论】：

Thanx 再次工作得很好......像往常一样。将使用这个，更压缩的代码。

【解决方案2】：

试试这个 awk 单行代码：

 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

想法是，使用gsub() 为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"。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"

【讨论】：