Mongodb merge chunk with $maxkey value on sharded cluster - mongodb

Question

I have shardkey {thread_id:1,_id:1} on collection "post",
and i want to merge 2 following chunk :
{
"_id" : "forum.post-thread_id_\"547dc7c2de2cf22b688b4572\"_id_ObjectId('549c519660e24b65118b456c')",
"lastmod" : Timestamp(3012, 3),
"lastmodEpoch" : ObjectId("50829c0e172de38a3398f72c"),
"ns" : "forum.post",
"min" : {
"thread_id" : "547dc7c2de2cf22b688b4572",
"_id" : ObjectId("549c519660e24b65118b456c")
},
"max" : {
"thread_id" : ObjectId("50901d4e1dd7198161000063"),
"_id" : ObjectId("50901d4e1dd7198161000068")
},
"shard" : "shard3"
}
{
"_id" : "forum.post-thread_id_ObjectId('50901d4e1dd7198161000063')_id_ObjectId('50901d4e1dd7198161000068')",
"lastmod" : Timestamp(604, 0),
"lastmodEpoch" : ObjectId("50829c0e172de38a3398f72c"),
"ns" : "forum.post",
"min" : {
"thread_id" : ObjectId("50901d4e1dd7198161000063"),
"_id" : ObjectId("50901d4e1dd7198161000068")
},
"max" : {
"thread_id" : {
"$maxKey" : 1
},
"_id" : {
"$maxKey" : 1
}
},
"shard" : "shard3"
}
It need to merge because thread_id supposed to be string , with current condition 1st chunk hold all new data (string -> ObjectId()), and 2nd chunk only hold documents with thread_id "ObjectId()"
I have tried this command :
reference
db.runCommand({
mergeChunks : 'forum.post',
bounds : [{
thread_id : "547dc7c2de2cf22b688b4572",
_id : ObjectId("549c519660e24b65118b456c")
}, {
thread_id : {
$type : 127
},
_id : {
$type : 127
}
}
]
})
And i got this error :
{
"ok" : 0,
"errmsg" : "shard key bounds [{
thread_id: " 547dc7c2de2cf22b688b4572 ",
_id: ObjectId(" 549c519660e24b65118b456c ")
},{
thread_id: { $type: 127 }, _id: { $type: 127 } })
are not valid for shard key pattern { thread_id: 1.0, _id: 1.0 }"
}
Does anyone know how to fix this ?
Mongodb Version 2.4.9

Answer 1

It appear that "mergechunk" command was on later version 2.6.x ++
I solved my problem using this command :
db.runCommand({
mergeChunks : 'forum.post',
bounds : [{
thread_id : "547dc7c2de2cf22b688b4572",
_id : ObjectId("549c519660e24b65118b456c")
}, {
thread_id : MaxKey,
_id : MaxKey
}
]
})
it appear that for "write" we should use :
db.foo.insert({ id : MaxKey });
For "Query" we should use :
db.foo.find({ id : { $type : 127 } });