Columns 1 and 3 are of concern, I first want to consolodate column 3, 
and then sort again by column 1

BEFORE SORT:

col1 col2 col3 col4 col5
12    z    d    r    4
13    z    c    r    4
14    z    d    r    4 
15    z    c    r    4



AFTER SORT:

col1 col2 col3 col4 col5
12    z    d    r    4
14    z    d    r    4 
13    z    c    r    4
15    z    c    r    4
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