使用awk在.CSV逗号分隔文件中添加双引号

Question

嗨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文件中拿到8场昏迷界定如下：

'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 

正如你看到的第一个3场是单引号之间，4日是空白，单引号和6日至8日分隔仅逗号之间的第5位。 我希望得到以下结果（也第四场即使空需要用双引号）：

"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" 

我部分从而以混合结果sed和awk：

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

但第四场不是双引号，我需要尽可能减少精化时间。 无论如何，帮助AWK以更好的表现来完成所有的事情，并且还有第四场双引号。 许多thx的帮助。 M.Tave

Answer 1

如果您的数据是真的没有嵌入引号，换行符或任何简单的，那么所有你需要的是：

$ 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" 

Answer 2

给这个AWK的一行一试：

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 

的想法是，用gsub()到双引号添加到那些非空字段。那些空的领域，只需将"添加到头部和尾部。替换正则表达式被定义为脚本外部的awk变量，用于避免转义。

它与输入数据在这里：

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"