无法在 mongodb 中对已经填充的集合进行分片

Question

我运行命令以使用此命令对集合进行分片

sh.shardCollection("db.collection_name",{"_id":"hashed"})

我得到以下错误

{
    "ok" : 0.0,
    "errmsg" : "Please create an index that starts with the proposed shard key before sharding the collection",
    "code" : 72,
    "codeName" : "InvalidOptions",
    "operationTime" : Timestamp(1582011118, 65),
    "$clusterTime" : {
        "clusterTime" : Timestamp(1582011118, 65),
        "signature" : {
            "hash" : { "$binary" : "jOIjTJkZKkC2ZI5lFQwX4Q7QNfs=", "$type" : "00" },
            "keyId" : NumberLong(6774859010160984065)
        }
    }
}

已经有索引

_id

    {
        "v" : 2,
        "key" : {
            "_id" : 1
        },
        "name" : "_id_",
        "ns" : "db.collection_name"
    }

我正在运行 Mongo 4.0.0 分片集群设置

Answer 1

如果你正在分片已经填充的集合。那你应该试试 :

我有数据库测试和集合名称作为人。基本上你需要创建一个索引来分片已经填充的集合。从集合中选择密钥并对其进行散列

mongos> db.people.createIndex({ "user_id" : "hashed" }) /// 
                                    db.collection.createIndex({ "key" : "hashed"})
{
        "raw" : {
                "foo/localhost:27017,localhost:27018,localhost:27019" : {
                        "createdCollectionAutomatically" : false,
                        "numIndexesBefore" : 4,
                        "numIndexesAfter" : 5,
                        "ok" : 1
                }
        },
        "ok" : 1,
        "operationTime" : Timestamp(1593154931, 1),
        "$clusterTime" : {
                "clusterTime" : Timestamp(1593154931, 1),
                "signature" : {
                        "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="),
                        "keyId" : NumberLong(0)
                }
        }


mongos> sh.shardCollection("test.people", { "user_id": "hashed" })
{
        "collectionsharded" : "test.people",
        "collectionUUID" : UUID("4ee30d04-8dc9-43dc-94f6-a898bc96da89"),
        "ok" : 1,
        "operationTime" : Timestamp(1593154958, 11),
        "$clusterTime" : {
                "clusterTime" : Timestamp(1593154958, 11),
                "signature" : {
                        "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="),
                        "keyId" : NumberLong(0)
                }
        }
}

mongos> sh.isBalancerRunning()

真实

希望对您有所帮助！

Answer 2

感谢 Neha 分享步骤。我有类似的情况，并且能够使用上述步骤进行补救