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In a simple scenario of me inserting a key-value pair, when value contains some white space, how can I preserve it?


> >{"name":"mike    "})
> > { "_id" : ObjectId("5080c03b8410d443d9acb7f5"), "name" : "mike " }
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up vote 2 down vote accepted

A bit of testing shows that the data is being inserted correctly, but the shell is trimming the field when it displays it. You can test this as follows:

mongos> db.test.insert({"name":"    adam    "})
mongos> db.test.find({"name":"    adam    "})
{ "_id" : ObjectId("50814e5c2a17d922cd25974f"), "name" : " adam " }
mongos> db.test.find({"name":" adam "})

That is, the data is found when you query with multiple spaces but not found when you re-use what the shell displays. So this is just a display issue with the shell, the DB is behaving as it should behind the scenes. Also tested this with a driver and it behaved correctly.

Even though this means that the data is the way you want, it is still technically a bug, because it could be confusing. So I filed a bug here:

Finally, to make this print out correctly, try this (assuming the same data I used in my test):

mongos> var fix = db.test.find({"name":"    adam    "}).next()
mongos> printjsononeline(fix)
{  "_id" : ObjectId("50814e5c2a17d922cd25974f"),  "name" : "    adam    " }
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Thank you Adam! – Jam Oct 19 '12 at 14:14
welcome! I just updated to add that I have filed a bug for the display issue :) – Adam C Oct 19 '12 at 14:38

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