String replace ' for mySQL insert

[Roland Klein overmeer]

Hello All,

I'm a newbie, just started programming Ruby about 1 month ago. Have lots
of experience with vb so the programming concepts are clear to me. I'm
building a script that is using the sample stream of the Twitter API and
insert it into MySQL for analysis. The problem is, that some of the
tweets have a ' in them. I want to replace them with '' so insert into
SQL is not a problem. I have written some piece of code trying to get
this to work, but the output replaces every letter with ''. This is the
code:

if line.include?"'"
result=""
teller=line.length-1
for i in 1..teller do
if line="'"
result=result + "''"
else
result=result + line
end
end
line=result
end

What am I doing wrong?

Thanks,
Roland

 

[Brian Candler]

Roland Klein overmeer wrote in post #977069:

I'm a newbie, just started programming Ruby about 1 month ago. Have lots
of experience with vb so the programming concepts are clear to me. I'm
building a script that is using the sample stream of the Twitter API and
insert it into MySQL for analysis. The problem is, that some of the
tweets have a ' in them. I want to replace them with '' so insert into
SQL is not a problem. I have written some piece of code trying to get
this to work, but the output replaces every letter with ''. This is the
code:

You're probably going about this the wrong way - your database layer
should provide a quoting mechanism for you. For example, if you're using
the low-level mysql-ruby then use Mysql.quote(str); if you're using
something like ActiveRecord then that handles quoting for you.

But to answer your direct question:

line.gsub!("'","''")

would achieve what you're asking for.

 

[Roland Klein overmeer]

Thanks Brian,

for the eyeopener (and a quick fix)!

 

[Ian M. Asaff]

[Note: parts of this message were removed to make it a legal post.]

in VB, '=' can means both assignment and equality, so the following does
what you expect:

if line="'"

in ruby, you want '==' for equality (and '=' for assignment), so the above
line should be

if line=="'"

On Mon, Jan 24, 2011 at 4:17 AM, Roland Klein overmeer <

Hello All,

I'm a newbie, just started programming Ruby about 1 month ago. Have lots
of experience with vb so the programming concepts are clear to me. I'm
building a script that is using the sample stream of the Twitter API and
insert it into MySQL for analysis. The problem is, that some of the
tweets have a ' in them. I want to replace them with '' so insert into
SQL is not a problem. I have written some piece of code trying to get
this to work, but the output replaces every letter with ''. This is the
code:

if line.include?"'"
result=""
teller=line.length-1
for i in 1..teller do
if line="'"
result=result + "''"
else
result=result + line
end
end
line=result
end

What am I doing wrong?

Thanks,
Roland

 

[Roland Klein overmeer]

thanks Ian,

Essential knowledge for the future!