how to convert field to lower case in script?

[rl]

I am trying to create a lower case version of a field in all my documents.  I tried toLower(), toLowerCase(), $toLower, etc.. but none work.  I searched around and couldn't find any docs on how to do it (at least correct documentation that worked)

db.mydb.find().forEach(function(doc) {

doc.lname = doc.name.toLower();

db. mydb.save(doc);

})

TypeError: doc.name.toLower is not a function

[Wes Freeman]

You said you tried it, but toLowerCase() worked for me.

> db.test.save({name:"TEST"});
> db.test.find().forEach(function(doc) {
... doc.lname = doc.name.toLowerCase();
... db.test.save(doc);
... });
> db.test.find();
{ "_id" : ObjectId("4f653c644b0a7cc12e0b3ea3"), "name" : "TEST",
"lname" : "test" }

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[rl]

It's still not working for me...

MongoDB shell version: 2.0.3

connecting to: test

> db.mydb.find().forEach(function(doc) {

...  doc.lname = doc.name.toLowerCase();

...  db.mydb.save(doc);

... });

Sun Mar 18 01:57:49 TypeError: doc.name.toLowerCase is not a function (shell):2

> 

[Scott Hernandez]

Is name a string in *all* your docs?

You may want to check it before calling toLowerCase.

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[rl]

It should be.  How would I test it to be sure?

FYI - I tried this:

> db.mydb.find({"name":null}).limit(1);

which returned 0 records...

[rl]

I am running this query now.  I assume this is what you wanted me to try?

> db.mydb.find( { name : { $not: { $type : 2 } }} );

[Wes Freeman]

You can either do something like this:

if(doc.name != null) doc.lname = doc.name.toLowerCase();

or make the query like this:

db.mydb.find({name:{$exists:true}});

Wes

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[Wes Freeman]

You could also force it to be a string with something like this:
var strName = ""+doc.name;
doc.lname = strName.toLowerCase();

[H.J]

It would not caused by null value, but another types, such as
db.blog.insert({"name":["TEST",123]})
or
db.blog.insert({name:{id:"ABC",tags:"EFG"}})

follow is testing report:
> db.blog.insert({"name":["TEST",123]})
> db.blog.find().forEach(function(doc){
... doc.name = doc.name.toLowerCase();
... db.blog.save(doc);
... })
Sun Mar 18 10:32:51 TypeError: doc.name.toLowerCase is not a function (shell):2
> db.blog.remove()
> db.blog.insert({"name":null})
> db.blog.find().forEach(function(doc){
... doc.name = doc.name.toLowerCase();
... db.blog.save(doc);
... })
Sun Mar 18 10:33:18 TypeError: doc.name has no properties (shell):2

2012/3/18 Wes Freeman <freem...@gmail.com>:

--
红颜弹指老，刹那芳华！

[H.J]

strange that
{ name : { $not: { $type : 2 } }}
or
{ name : { $type : 4 } }
can't find the document
{"name":["TEST",123]}

any idea?

2012/3/18 H.J <shiy...@gmail.com>:

--
红颜弹指老，刹那芳华！

[Wes Freeman]

It shows up in {name: {$type:2}} -- weird.

This works, however:
> db.test.find().forEach(function(doc) {
... if(doc.name != null && typeof doc.name == "string") doc.lname =
doc.name.toLowerCase();
... db.test.save(doc);
... });

Wes