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$ join -t, file1.txt file2.txt | join -t, - file3.txt | cut -f 1,2,6,1 +0 -d, WSOMQAVPRA05,93.75,34.78,93.13 wsomdavpra03,90.39,69.04,68.85 wsomddvfxa01,39.22,92.44,46.97 wsompapgtw05,49.6,48.77,30.66