I am using mongoDB shell with version 3.0.2
I am trying to ensure uniqueness constraint over a username field in collection users.
This is what I gave:
db.users.ensureIndex({"username": 1},{unique: true})
It gave me following error:
{
"createdCollectionAutomatically" : false,
"numIndexesBefore" : 1,
"errmsg" : "exception: E11000 duplicate key error index: mybackend.users.$username_1 dup key: { : \"rahat\" }",
"code" : 11000,
"ok" : 0
}
Then i used, dropDups: true in the command:
db.users.ensureIndex({"username": 1},{unique: true, dropDups: true})
Then too I get the same error:
{
"createdCollectionAutomatically" : false,
"numIndexesBefore" : 1,
"errmsg" : "exception: E11000 duplicate key error index: mybackend.users.$username_1 dup key: { : \"rahat\" }",
"code" : 11000,
"ok" : 0
}
I also saw this SO link but here it already had one index. Mine does not have one.
db.users.getIndexes() ->
[
{
"v" : 1,
"key" : {
"_id" : 1
},
"name" : "_id_",
"ns" : "mybackend.users"
}
]
I looked for this issue on github and restarted the mongo but to no use. What am I doing wrong? I think I am doing a silly mistake. Please help.
The drop duplicates functionality on index creation is no longer supported since Mongo version 3.0. See the compatibility changes page for the 3.0 release.
Related
I am new in MongoDB and did an import of DB to my local. I get the following error after running my node app.
(node:1592) UnhandledPromiseRejectionWarning: Unhandled promise rejection (rejection id: 1): MongoError: exception: Index with name: expires_1 already exists with different options
I logged in to the mongo console and got the following indexes for collection - Session
Indexes for sessions:
[
{
"v" : 1,
"key" : {
"_id" : 1
},
"name" : "_id_",
"ns" : "db_staging.sessions"
},
{
"v" : 1,
"key" : {
"expires" : 1
},
"name" : "expires_1",
"ns" : "db_staging.sessions",
"background" : true
}
]
And then I got another same index name under system.indexes
Can I remove the duplicate key from system.indexes.
Any suggestion is highly appreciated. Thanks in advance.
Try delete all datas in indexes.
In SSH session 1, I have ran operation to create partial index in MongoDB as follows:
db.scores.createIndex(
... { event_time: 1, "writes.k": 1 },
... { background: true,
... partialFilterExpression: {
... "writes.l_at": null,
... "writes.d_at": null
... }});
The creation of the index is quite large and lasts about 30+ minutes. While it is still running I started SSH session 2.
In SSH session 2 to cluster, I described indexes on my collection scores, and it looks like it is already there...
db.scores.getIndexes()
[
...,
{
"v" : 1,
"key" : {
"event_time" : 1,
"writes.k" : 1
},
"name" : "event_time_1_writes.k_1",
"ns" : "leaderboard.scores",
"background" : true,
"partialFilterExpression" : {
"writes.l_at" : null,
"writes.d_at" : null
}
}
]
When trying to count with hint to this index, I get below error:
db.scores.find().hint('event_time_1_writes.k_1').count()
2019-02-06T22:35:38.857+0000 E QUERY [thread1] Error: count failed: {
"ok" : 0,
"errmsg" : "error processing query: ns=leaderboard.scoresTree: $and\nSort: {}\nProj: {}\n planner returned error: bad hint",
"code" : 2,
"codeName" : "BadValue"
} : _getErrorWithCode#src/mongo/shell/utils.js:25:13
DBQuery.prototype.count#src/mongo/shell/query.js:383:11
#(shell):1:1
Never seen this below, but need confirmation to check if its failing because indexing is still running ?
Thanks!
I want to create Index by ensureIndex at name with parameter:dropDups,cause my collection books has two documents' name is "0book".
db.books.ensureIndex({name:1},{unique:true,dropDups:true})
{
"createdCollectionAutomatically" : false,
"numIndexesBefore" : 1,
"errmsg" : "exception: E11000 duplicate key error index:
foobar.books.$name_1 dup key: { : \"0book\" }",
"code" : 11000,
"ok" : 0
}
Otherwise,it alerts me to the errmsg as above.
I don't know how to use pramater "dropDups",when create index in mongodb
I'm looking at our Mongo (2.4.10) indexes, using collection.getIndexes(). I see options that aren't discussed in any doc I can find. Specifically, I see the options "safe" and "force". For example below:
{
"v" : 1,
"name" : "status_1",
"key" : {
"status" : NumberLong(1)
},
"ns" : "db.mycoll",
"force" : true,
"background" : true
},
What do "force" and "safe" mean?
The options you mention ("force" and "safe") are not valid index options for MongoDB 2.4.
They likely resulted from a developer accidentally ensuring an index including these as index options (perhaps having intended for those fields to be part of the index criteria?).
You can reproduce this outcome in the mongo shell:
> db.foo.ensureIndex({foo: true}, {force: true, safe: true})
{
"createdCollectionAutomatically" : true,
"numIndexesBefore" : 1,
"numIndexesAfter" : 2,
"ok" : 1
}
> db.foo.getIndexes()
[
{
"v" : 1,
"key" : {
"_id" : 1
},
"name" : "_id_",
"ns" : "stack.foo"
},
{
"v" : 1,
"key" : {
"foo" : true
},
"name" : "foo_true",
"ns" : "stack.foo",
"force" : true,
"safe" : true
}
]
>
Unknown index options will be ignored (at least as at MongoDB 3.0), so while this is confusing the impact is currently benign. Unfortunately the only way to remove the invalid options would be dropping & rebuilding the affected index(es) as there is no API for changing an existing index.
It's possible that index option validation may be added in a future MongoDB release, but this should be noted as a compatibility change in the release notes. For example, MongoDB 2.6 has several index changes including better field name validation and enforcement of index key length.
I have a collection with the _id field as a IP with type String.
I'm using mongoose, but here's the error on the console:
$ db.servers.remove()
$ db.servers.insert({"_id":"1.2.3.4"})
$ db.servers.insert({"_id":"1.2.3.5"}) <-- Throws dup key: { : null }
Likely, it's because you have an index that requires a unique value for one of the fields as shown below:
> db.servers.remove()
> db.servers.ensureIndex({"name": 1}, { unique: 1})
> db.servers.insert({"_id": "1.2.3"})
> db.servers.insert({"_id": "1.2.4"})
E11000 duplicate key error index: test.servers.$name_1 dup key: { : null }
You can see your indexes using getIndexes() on the collection:
> db.servers.getIndexes()
[
{
"v" : 1,
"key" : {
"_id" : 1
},
"ns" : "test.servers",
"name" : "_id_"
},
{
"v" : 1,
"key" : {
"name" : 1
},
"unique" : true,
"ns" : "test.servers",
"name" : "name_1"
}
]
I was confused by exactly the same error today, and later figured it out. It was because I removed a indexed property from a mongoose schema, but did not drop that property from the mongodb index. The error message is infact that the new document has an indexed property whose value is null (not in the json).