Perl Mongo 查找对象 ID [英] Perl Mongo find object Id
问题描述
你会认为这是一件简单的事情.我有一个在我的收藏中的对象 ID 列表.我想根据对象 ID 获取单个记录.用谷歌搜索过,但没有任何帮助.
You would think it is a simple thing. I have a list of object id's that are in my collection. I would like to get a single record based on an object id. Have Googled, but nothing helpful.
所以我有对象 ID:5106c7703abc120a04070b34
So I have object id: 5106c7703abc120a04070b34
my $client = MongoDB::MongoClient->new;
my $db = $client->get_database( 'myDatabase' );
my $id_find = $db->get_collection('mycollection')->find({},{_id => MongoDB::OID->new(value => "5106c7703abc120a04070b34")});
print Dumper $id_find;
打印:
$VAR1 = bless( {
'_skip' => 0,
'_ns' => 'MindCrowd_test.Users',
'_grrrr' => 0,
'partial' => 0,
'_query' => {},
'_tailable' => 0,
'_client' => bless( {
'w' => 1,
'query_timeout' => 30000,
'find_master' => 0,
'_servers' => {},
'sasl' => 0,
'wtimeout' => 1000,
'j' => 0,
'timeout' => 20000,
'sasl_mechanism' => 'GSSAPI',
'auto_connect' => 1,
'auto_reconnect' => 1,
'db_name' => 'admin',
'ssl' => 0,
'ts' => 0,
'inflate_dbrefs' => 1,
'port' => 27017,
'host' => 'mongodb://localhost:27017',
'dt_type' => 'DateTime',
'max_bson_size' => 16777216
}, 'MongoDB::MongoClient' ),
'_limit' => 0,
'slave_okay' => 0,
'_request_id' => 0,
'immortal' => 0,
'started_iterating' => 0
}, 'MongoDB::Cursor' );
我尝试了上述发现的不同版本.所有这些都无法编译:
I have tried different verions of the above find. All of them fail to compile:
$mongo->my_db->my_collection(find({_id => "ObjectId(4d2a0fae9e0a3b4b32f70000"}));
$mongo->my_db->my_collection(
find({_id => MongoDB::OID->new(value => "4d2a0fae9e0a3b4b32f70000")}));
find({ _id => MongoDB::OID->new(value => "4d2a0fae9e0a3b4b32f70000")}) );
它们都不起作用.如何使用对象 ID 查找(findone)单个记录??
NONE of them work. How do I find (findone) a single record using the object id??
推荐答案
find 方法返回一个用于迭代的 Cursor 对象.如果您只想要一条记录,请使用返回值的 find_one 方法.
the find methods returns a Cursor object for iterating through. If you only want one record use the find_one method which returns a value.
my $client = MongoDB::MongoClient->new;
my $db = $client->get_database( 'myDatabase' );
my $id_find = $db->get_collection('mycollection')->find_one({_id => MongoDB::OID->new(value => "5106c7703abc120a04070b34")});
print Dumper $id_find;
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