Question

我有以下文件，

total.txt

order1,5,item1
order2,6,item2
order3,7,item3
order4,6,item4
order8,9,item8

changed.txt

order3,8,item3
order8,12,item8

total.txt是总订单数据并且已更改.txt是最近更改的数据。我想将最近的变化与总和合并，我希望输出为，

Output.txt的

order1,5,item1
order2,6,item2
order3,8,item3
order4,6,item4
order8,12,item8

注意：total.txt的第（3＆amp; 5th）行的第2列用changed.txt文件更新

我已使用下面的nawk来比较第一个coulmn，但无法将其打印到输出文件。请帮助完成以下命令

nawk -F"," 'NR==FNR {a[$1]=$2;next} ($1 in a) "print??"' total.txt changed.txt

Answer 1

另一个awk

awk -F, 'FNR==NR {a[$1]=$0;next} {print (a[$1]?a[$1]:$0)}' changed.txt total.txt
order1,5,item1
order2,6,item2
order3,8,item3
order4,6,item4
order8,12,item8

它是如何运作的？

awk -F, '                       # set field separator to ","
    FNR==NR {                   # run this only on first file "changed.txt"
        a[$1]=$0                # store "changed.txt" in array "a" using first field as index
        next                    # skip to next record
    }
        {                       # run this when second file is read "total.txt"
        print (a[$1]?a[$1]:$0)  # if filed exist in "changed" use that, else use "total"
    }' changed.txt total.txt    # read these files

Answer 2

这可能适合你（GNU sed）：

sed -r 's/^([^,]*,).*/s|^\1.*|&|/' changed.txt | sed -f - total.txt > output.txt

Answer 3

这个单行为你工作吗？

awk -F, 'NR==FNR{a[$1]=$0;next}a[$1]{$0=a[$1]}7' change total

试验：

kent$  head c t
==> c <==
order3,8,item3
order8,12,item8

==> t <==
order1,5,item1
order2,6,item2
order3,7,item3
order4,6,item4
order8,9,item8

kent$  awk -F, 'NR==FNR{a[$1]=$0;next}a[$1]{$0=a[$1]}7' c t
order1,5,item1
order2,6,item2
order3,8,item3
order4,6,item4
order8,12,item8

Answer 4

读取第一个changed.txt文件并将数据保存在哈希中。然后比较是否存在total.txt的第一个字段并替换值：

awk '
    BEGIN { FS = OFS = "," } 
    NR == FNR { a[$1] = $2; next } 
    { if ( $1 in a ) { $2 = a[$1] } print }
' changed.txt total.txt

它产生：

order1,5,item1
order2,6,item2
order3,8,item3
order4,6,item4
order8,12,item8

比较两个文件并合并数据

4 个答案: