Question

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Hi everyone!

I need to replace some values in FILE2 file with the values on FILE1 file when date and time match.

FILE1

121216, 0100, 1.1,
121216, 0115, 1.0,
121216, 0130, 2.1,
121216, 0145, 1.8,
121216, 0200, 1.5,
121216, 0215, 1.3,
121216, 0230, 0.9,
121216, 0245, 1.2,

FILE2

121216, 0100, 2.3,
121216, 0200, ,

OUTPUT

121216, 0100, 1.1,
121216, 0200, 1.5,

Please an awk solution, speed is needed.

Thanks in advance!

Answer 1

One way:

 awk -F, 'NR==FNR{a[$1$2]=$3;next}{$3=a[$1$2];}1' OFS=, file1 file2