Sed: replace first occurrence of a string in every line

find and replacesed

Imagine I have a file like this:

INSERT INTO table VALUES('1','<p><em>The lazy fox jumps again</em></p>bunch of other html<p><em>Is the lazy fox crazy?</em></p>')
INSERT INTO table VALUES('2','<p><em>The lazy fox jumps again</em></p>bunch of other html<p><em>Is the lazy fox crazy?</em></p>')
INSERT INTO table VALUES('3','<p><em>The lazy fox jumps again</em></p>bunch of other html<p><em>Is the lazy fox crazy?</em></p>')

And I wish to delete only the first occurrence of <p><em> and </em></p> so I end up with something like this:

INSERT INTO table VALUES('1','The lazy fox jumps againbunch of other html<p><em>Is the lazy fox crazy?</em></p>')
INSERT INTO table VALUES('2','The lazy fox jumps againbunch of other html<p><em>Is the lazy fox crazy?</em></p>')
INSERT INTO table VALUES('3','The lazy fox jumps againbunch of other html<p><em>Is the lazy fox crazy?</em></p>')

… how can I do that with sed (or perl)? The statement…:

sed "1,/INSERT INTO/s/<p><em>//g"

… only replaces the first occurrence in the file, not on every line.

Help is much appreciated.

Best Answer

  • If you want to process all lines with INSERT INTO, do not provide address range. If you want to only replace the first occurence of a string, do not provide /g:

    sed -e '/INSERT INTO/s/<p><em>//' -e '/INSERT INTO/s/<\/em><\/p>//'