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43 lines
1.3 KiB
Plaintext
43 lines
1.3 KiB
Plaintext
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====== Using ''awk'' to deal with CSV that uses quoted/unquoted delimiters ======
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---- dataentry snipplet ----
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snipplet_tags : awk, csv
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LastUpdate_dt : 2010-07-31
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Contributors : SiegX (IRC)
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type : snipplet
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----
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CSV files are a mess, yes.
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Assume you have CSV files that use the comma as delimiter and quoted data fields that can contain the delimiter.
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<code>
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"first", "second", "last"
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"fir,st", "second", "last"
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"firtst one", "sec,ond field", "final,ly"
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</code>
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Simply using the comma as separator for ''awk'' won't work here, of course.
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Solution:
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Use the field separator ''", "|^"|"$'' for ''awk''.
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This is an OR-ed list of 3 possible separators:
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|''", "''|matches the area between the datafields|
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|''^"''|matches the area left of the first datafield|
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|''"$''|matches the area right of the last data field|
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You can tune these delimiters if you have other needs (for example if you don't have a space after the commas).
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Test:
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The ''awk'' command used for the CSV above just prints the fileds separated by ''###'' to see what's going on:
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<code>
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$ awk -v FS='", "|^"|"$' '{print $2"###"$3"###"$4}' data.csv
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first###second###last
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fir,st###second###last
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firtst one###sec,ond field###final,ly
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</code>
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**ATTENTION** If the CSV data changes its format every now and then (for example it only quotes the data fields if needed, not always), then this way will not work.
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