Jeśli jeszcze macie ochotę brnąć w to wszystko dalej ;-)

Tabelka z danymi:
<code>
testm=# select * from testcollection;
 id |         name         |        sname         |  age
----+----------------------+----------------------+--------
  1 | LEeUk6sCZhquTlm9hVW3 | LjFxXYpRWNdIjmtHMbec |  82232
  2 | Z1Q72WqWVCNW732jtNeH | k5GBun59KUgbHU0b0JFr | 161315
  3 | 1ZjJjveDNJBsDGW1mlxP | OjEgiWJ7FKjbl8fJg1Cg | 935744
  4 | YZSKWScWM2OPpHe8LZix | tSGCE4xWLiMUZLM6aYJX | 106394
  5 | xnCgXTU0eABr4T264N28 | xaaQc3PNKwtYa91qfK7w | 715951
  6 | OZ0T7eXjJ1cO7aMn8Dwi | lwUP7g1w8RB4Ibm3PZ0G | 444402
  7 | VBaUi8QBSGq4mq3EX4W8 | qqXfqlZHXGFkSyG7OQo0 |  15788
  8 | 2XB9xhbJaRkGWeQwaxrO | QdX5wZMpPGkew8zW8xEG | 425219
  9 | 9aTOrhBAzj7WPHixx00i | nC2SjU5RnDYbrEU83Ufl | 839914
 10 | pFMkX6nrQn9H3mCsnwjp | USNg3gWC3L830NsXKYEg | 385078
</code>

W Mongo te same dane.

Zapytanie w postgresie generuje poprawne wyniki:
<code>
select name, sname, age from testcollection where name <= 'YZSKWScWM2OPpHe8LZix' ORDER BY name LIMIT 10 OFFSET 3
LEeUk6sCZhquTlm9hVW3 LjFxXYpRWNdIjmtHMbec 82232
OZ0T7eXjJ1cO7aMn8Dwi lwUP7g1w8RB4Ibm3PZ0G 444402
pFMkX6nrQn9H3mCsnwjp USNg3gWC3L830NsXKYEg 385078
VBaUi8QBSGq4mq3EX4W8 qqXfqlZHXGFkSyG7OQo0 15788
xnCgXTU0eABr4T264N28 xaaQc3PNKwtYa91qfK7w 715951
YZSKWScWM2OPpHe8LZix tSGCE4xWLiMUZLM6aYJX 106394
</code>

Analogiczne zapytanie w Mongo zwraca takie dane:
<code>
{ "_id" : { "$oid" : "5835eff09dd4e4442c4d1091" }, "name" : "LEeUk6sCZhquTlm9hVW3", "sname" : "LjFxXYpRWNdIjmtHMbec", "age" : 82232 }
{ "_id" : { "$oid" : "5835eff09dd4e4442c4d1096" }, "name" : "OZ0T7eXjJ1cO7aMn8Dwi", "sname" : "lwUP7g1w8RB4Ibm3PZ0G", "age" : 444402 }
{ "_id" : { "$oid" : "5835eff09dd4e4442c4d1097" }, "name" : "VBaUi8QBSGq4mq3EX4W8", "sname" : "qqXfqlZHXGFkSyG7OQo0", "age" : 15788 }
{ "_id" : { "$oid" : "5835eff09dd4e4442c4d1094" }, "name" : "YZSKWScWM2OPpHe8LZix", "sname" : "tSGCE4xWLiMUZLM6aYJX", "age" : 106394 }
</code>
Tak jakby zabrakło tych, gdzie pole name zaczyna się od małych liter.

Ale w innym zapytaniu (tzn w odpowiedniku tego zapytania w mongo):
<code>
select name, sname, age from testcollection where name <= 'pFMkX6nrQn9H3mCsnwjp' ORDER BY name LIMIT 10 OFFSET 3
</code>

Wyniki takie:
<code>
{ "_id" : { "$oid" : "5835eff09dd4e4442c4d1091" }, "name" : "LEeUk6sCZhquTlm9hVW3", "sname" : "LjFxXYpRWNdIjmtHMbec", "age" : 82232 }
{ "_id" : { "$oid" : "5835eff09dd4e4442c4d1096" }, "name" : "OZ0T7eXjJ1cO7aMn8Dwi", "sname" : "lwUP7g1w8RB4Ibm3PZ0G", "age" : 444402 }
{ "_id" : { "$oid" : "5835eff09dd4e4442c4d1097" }, "name" : "VBaUi8QBSGq4mq3EX4W8", "sname" : "qqXfqlZHXGFkSyG7OQo0", "age" : 15788 }
{ "_id" : { "$oid" : "5835eff09dd4e4442c4d1094" }, "name" : "YZSKWScWM2OPpHe8LZix", "sname" : "tSGCE4xWLiMUZLM6aYJX", "age" : 106394 }
{ "_id" : { "$oid" : "5835eff09dd4e4442c4d1092" }, "name" : "Z1Q72WqWVCNW732jtNeH", "sname" : "k5GBun59KUgbHU0b0JFr", "age" : 161315 }
{ "_id" : { "$oid" : "5835eff09dd4e4442c4d109a" }, "name" : "pFMkX6nrQn9H3mCsnwjp", "sname" : "USNg3gWC3L830NsXKYEg", "age" : 385078 }
</code>


Opcje buduję tak:
<code>
        auto order = bsoncxx::builder::stream::document() << "name" << 1 << bsoncxx::builder::stream::finalize;
        auto opts = mongocxx::options::find();
        opts.sort(order.view());
        opts.limit(10);
        opts.skip(3);
</code>

Zapytanie budję tak:
<code>
            mongocxx::cursor cursor = collection.find(
                bsoncxx::builder::stream::document()       <<
                "name"                                     <<
                bsoncxx::builder::stream::open_document   <<
                           "$lte"                         <<
                           trios[i].name                  <<
                bsoncxx::builder::stream::close_document  <<
                bsoncxx::builder::stream::finalize
                ,
                opts
            );
</code>

Widzicie jakiś bląd? Ja póki co nie widzę.

Pozdrawiam