在bash脚本中使用awk实现vlookup功能

以下是输入：

文件1.csv

文件2.csv

预期产出：

文件3.csv

目前正在尝试使用join

join -a1 -t '|' -1 1 -2 1 -o 1.1,2.2,1.2,1.3 file1.csv file2.csv > file3.csv

但它发现一些行没有匹配，所以我将我的概念转变为对这两个文件使用最有可能的vlookup功能。请帮忙

---

谢谢大家

请您尝试使用GNU

awk

编写和测试的

awk

并显示样本

awk '
BEGIN{
  FS=OFS="|"
}
FNR==NR{
  arr[$1]=$2
  next
}
($1 in arr){
  $1=($1 OFS arr[$1])
}
1
' file2.csv file1.csv

说明：添加上述内容的详细说明

awk '                  ##Starting awk program from here.
BEGIN{                 ##Starting BEGIN section from here of this program.
  FS=OFS="|"           ##Setting | as field separator and output field separator.
}
FNR==NR{               ##Checking condition if FNR==NR which will be TRUE when file2.csv is being read.
  arr[$1]=$2           ##Creating arr with index of 1st field and value of 2nd field.
  next                 ##next will skip all further statements from here.
}
($1 in arr){           ##checking condition if $1 is present in arr then do following.
  $1=($1 OFS arr[$1])  ##Saving current $1 OFS and value of arr with index of $1 in $1.
}
1                      ##1 will print the current line.
' file2.csv file1.csv  ##Mentioning Input_file names here.

---

我测试了您提供的

join

命令，我认为它在我的机器上产生了预期的输出（FreeBSD 12.2-RELEASE）：

---

您可能需要首先对两个文件的要连接的列进行排序（或者在这种情况下，如果您连接了第一列，那么整行也应该工作），即

join-a1-t'|'-11-21-o1.1,2.2,1.2,1.3，似乎预期输出中缺少包含
ddd
的行。不确定这是不是故意的？否则，您的
join
命令似乎可以工作…在侧节点上，它是
files1
和
files3
，但仅是
file2
。
join -a1 -t '|' -1 1 -2 1 -o 1.1,2.2,1.2,1.3 file1.csv file2.csv > file3.csv

awk '
BEGIN{
  FS=OFS="|"
}
FNR==NR{
  arr[$1]=$2
  next
}
($1 in arr){
  $1=($1 OFS arr[$1])
}
1
' file2.csv file1.csv

awk '                  ##Starting awk program from here.
BEGIN{                 ##Starting BEGIN section from here of this program.
  FS=OFS="|"           ##Setting | as field separator and output field separator.
}
FNR==NR{               ##Checking condition if FNR==NR which will be TRUE when file2.csv is being read.
  arr[$1]=$2           ##Creating arr with index of 1st field and value of 2nd field.
  next                 ##next will skip all further statements from here.
}
($1 in arr){           ##checking condition if $1 is present in arr then do following.
  $1=($1 OFS arr[$1])  ##Saving current $1 OFS and value of arr with index of $1 in $1.
}
1                      ##1 will print the current line.
' file2.csv file1.csv  ##Mentioning Input_file names here.

21|A800|AAAAA|1023
21|A800|BBBBB|1203
21|A800|CCCCC|2533
22|B900|DDDDD|1294
22|B900|EEEEE|1249
22|B900|FFFFF|4129
22A|C1000|GGGGG|4121
22A|C1000|HHHHH|1284
31B|D1000|IIIII|5403
31B|D1000|JJJJJ|1249