how to replace a \' with '' using sed -

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i have file test.sql:

'here is' , \' other 'you'

and replace \' (escaped single quote) '' (2 singles quotes) postgres , leave other single quotes alone. how this. have tried:

mon mar 16$ sed -i.bak s/\'/''/g test.sql

but takes out single quotes.

your enemy in shell quoting. string

s/\'/''/g

is mangled shell before given sed. shell, '' empty string, , \' suppresses special meaning of single quotes (so quote actual single quote character). sed sees after processing is

s/'//g

...wich removes single quotes.

there several ways work around problem; 1 of them is

sed -i.bak "s/\\\\'/''/g" test.sql

inside doubly-quoted shell string, backslashes need escaped (exceptions exist). means "s/\\\\'/''/g" in shell command translates s/\\'/''/g argument sed. in sed regexes, backslashes need escaping, is, in fact, wanted happen: instances of \' replaced ''.


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