I just set the config like that:
http://talat.uyarer.com/post/121179803796/how-to-connect-hbase-using-apache-phoenix-from
but it does not work, and it show me the error:
I never used apache-phoenix, but in front of this type of error I'd first check if the driver is in the lib (I guess it is), then on the database connection parameters on the left panel). According to the error, I'd start with the Advanced/Prefered Schema name, and the Option/Parameter with a parameter name you have to drill from the apache-phoenix documentation.
Related
If have multiple databases defined on a particular ArangoDB server, how do I specify the database I'd like an AQL query to run against?
Running the query through the REST endpoint that includes the db name (substituted into [DBNAME] below) ie:
/_db/[DBNAME]/_api/cursor
doesn't seem to work. The error message says 'unknown path /_db/[DBNAME]/_api/cursor'
Is this something I have to specify in the query itself?
Also: The query I'm trying to run is:
FOR col in COLLECTIONS() RETURN col.name
Fwiw, I haven't found a way to set the "current" database through the REST API. Also, I'm accessing the REST API from C++ using fuerte.
Tom Regner deserves primary credit here for prompting the enquiry that produced this answer. I am posting my findings here as an answer to help others who might run into this.
I don't know if this is a fuerte bug, shortcoming or just an api caveat that wasn't clear to me... BUT...
In order for the '/_db/[DBNAME/' prefix in an endpoint (eg full endpoint '/_db/[DBNAME/_api/cursor') to be registered and used in the header of a ::arangodb::fuerte::Request, it is NOT sufficient (as of arangodb 3.5.3 and the fuerte version available at the time of this answer) to simply call:
std::unique_ptr<fuerte::Request> request;
const char *endpoint = "/_db/[DBNAME/_api/cursor";
request = fuerte::createRequest(fuerte::RestVerb::Post,endpoint);
// and adding any arguments to the request using a VPackBuilder...
// in this case the query (omitted)
To have the database name included as part of such a request, you must additionally call the following:
request->header.parseArangoPath(endpoint);
Failure to do so seems to result in an error about an 'unknown path'.
Note 1: Simply setting the database member variable, ie
request->header.database = "[DBNAME]";
does not work.
Note 2: that operations without the leading '/_db/[DBNAME]/' prefix, seem to work fine using the 'current' database. (which at least for me, seems to be stuck at '_system' since as far as I can tell, there doesn't seem to be an endpoint to change this via the HTTP REST Api.)
The docs aren't very helpful right now, so just incase someone is looking for a more complete example, then please consider the following code.
EventLoopService eventLoopService;
// adjust the connection for your environment!
std::shared_ptr<Connection> conn = ConnectionBuilder().endpoint("http://localhost:8529")
.authenticationType(AuthenticationType::Basic)
.user(?) // enter a user with access
.password(?) // enter the password
.connect(eventLoopService);
// create the request
std::unique_ptr<Request> request = createRequest(RestVerb::Post, ContentType::VPack);
// enter the database name (ensure the user has access)
request->header.database = ?;
// API endpoint to submit AQL queries
request->header.path = "/_api/cursor";
// Create a payload to be submitted to the API endpoint
VPackBuilder builder;
builder.openObject();
// here is your query
builder.add("query", VPackValue("for col in collections() return col.name"));
builder.close();
// add the payload to the request
request->addVPack(builder.slice());
// send the request (blocking)
std::unique_ptr<Response> response = conn->sendRequest(std::move(request));
// check the response code - it should be 201
unsigned int statusCode = response->statusCode();
// slice has the response data
VPackSlice slice = response->slices().front();
std::cout << slice.get("result").toJson() << std::endl;
I am currently attempting to use transactions in my C++ app, but I have a problem with the ODBC's auto commit mode.
I am using the POCO libaries to create a connection to a PostgreSQL database on the same machine. Currently, I can send data to this database as single statements, but I cannot get my head around how to use Poco's transaction libraries to be able to send this data more quickly.
As I have several thousand records to insert, and so continuing to use single insert statements is extrememly slow and inpractical - So I am trying to use Poco's transaction to speed this up a bit (a fair bit).
The error I am encountering is a theoretically a simple one - Poco is throwing the following error:
'Invalid access: Session is in auto commit mode.'
I understand, as a result of this, I should somehow set "auto commit" to false - as it only allows me to commit data to the database line by line, rather than as a single transaction.
The problem is how I set this.
Currently, I have a session created from Session.h, that looks alot like this:
session = new Poco::Data::Session(
"ODBC",
connection_data.str()
);
Where connection data is a simple stringstream with the login information, password, database, server and "Driver={PostgreSQL ANSI};" to tell ODBC to utilize PostgreSQL's driver.
I have tried just setting a property "autocommit" to false through the session's setFeature or setProperty settings, this, of course, was to no avail. (it was more of a ditch attempt at this point).
session->setFeature("AUTOCOMMIT", false);
Looking around, I saw a possible alternative method by creating a ODBC sessionImpl directly from ODBC/session/SessionImpl.h instead of using this generic method above, and then creating a new session object from this.
The benefits of this are that ODBC's sessionImpl has references to autocommit mode in the header, which would suggest it would be able to handle this:
void autoCommit(const std::string&, bool val);
/// Sets autocommit property for the session.
However, having not used sessionImpl before, I cannot garuntee if this will work or if can can get this to work with the limited documentation available.
I am using C++ 03 (Not 11), with Visual Studio 2015
Poco 1.7.5
Boost (Where needed)
Would any one know the correct way of setting this feature (above) or a alternative method to achieving this?
edit: Looking at the source of poco, at:
https://github.com/pocoproject/poco/blob/develop/Data/ODBC/src/SessionImpl.cpp#L153
The property seems be named autoCommit, and looking at
https://github.com/pocoproject/poco/blob/develop/Data/include/Poco/Data/AbstractSessionImpl.h#L120
the case of the property names seem to matter. So, does it help if you use session->setFeature("autoCommit", false);?
Cant you just call session->begin(); and session->end(); on the corresponding Session object?
What is returned by session->canTransact()?
According to the doc begin() will start a new transaction, the doc does not mention any property that needs to be set before or after.
See: https://pocoproject.org/docs/Poco.Data.Session.html
Also faced a similar issue.
First of all before begin() need:
m_ses.setFeature("autoCommit", false);
m_ses.begin();
And the second issue is that this feature stays "autoCommit" in false for all other sessions. So don't forget for the next session call
session.setFeature("autoCommit", true);
I am trying to access our AS400 database with Ruby on Rails, using the "dbi" gem and the "dbd-odbc" gem.
I have found this code to build off of. When I pass in the server address...
It seems that the original code uses an DSN, but I wanted to pass in the IP, database name, and library in the code to prevent any DSN being needed.
require 'dbi'
dbh = DBI.connect('DBI:ODBC:SYSTEM=<ip_address>;DBQ=<db_name>;DFTPKGLIB=<library_name>;LANGUAGEID=ENU', 'UID=<user_name>', 'PWD=<password>')
sth = dbh.prepare('select count(*) from my_table')
sth.execute
# Print out each row
while row=sth.fetch do
p row
end
sth.finish
dbh.disconnect
it gives me an error of...
DBI::InterfaceError: Unable to load driver 'ODBC'
what would be the correct syntax?
This works for me - also, just put your authentication portion inside of the first argument to the DBI.connect function:
First install the gems: dbi, dbd-odbc, ruby-odbc. I was getting the same error without the ruby-odbc gem
Then:
require 'odbc'
require 'dbi'
dbh = DBI.connect('DBI:ODBC:SYSTEM=MYAS400;DBQ=TABLE_NAME;DFTPKGLIB=SCHEMA_NAME;DRIVER=Client Access ODBC Driver (32-bit);LANGUAGEID=ENU;USERID=SUPERADMIN;PWD=SUPERSECURE')
I don't know exactly how that works in Ruby, but in the connection string I don't see where you mention the driver your trying to use to connect.
Seems like this line:
dbh = DBI.connect('DBI:ODBC:SYSTEM=<ip_address>;DBQ=<db_name>;DFTPKGLIB=<library_name>;LANGUAGEID=ENU', 'UID=<user_name>', 'PWD=<password>')
needs to be something like this to indicate the driver ODBC should use to connect:
dbh = DBI.connect('DBI:ODBC:Driver=iSeries Access ODBC Driver;SYSTEM=<ip_address>;DBQ=<db_name>;DFTPKGLIB=<library_name>;LANGUAGEID=ENU', 'UID=<user_name>', 'PWD=<password>')
I have a system service that handles print requests, and given a printer name from the user, attaches a DC to that printer. It starts a document, ends it, and detatches.
m_PrinterDC.CreateDC (L"WINSPOOL", _printerName.c_str(), NULL, NULL)
m_DC.Attach(m_hprinter)
m_DC.StartDoc(...)
...
mDc.TextOut(...)
...
m_DC.EndDoc()
m_DC.Detatch()
This works fine for normal printers, but when using the "Print to OneNote" functionality (driver name 'Send To OneNote 2010') it doesn't seem to work. I would like to avoid custom logic just for this feature; ideally all printers would work regardless. Any thoughts what might be going wrong? I've tried updating the printer security settings to include Print rights for group everyone; not sure what else to try.
Unfortunately, I have to guess some points, because you seem to avoid detailed description of error condition.
First, if you check all return values are success, just it may be a problem about onenote itself. Check the condition of onenote by printing using other programmes.
Second, did you check if _printerName is exact? If some of users are using other language OS, the driver name, 'Send To OneNote 2010' will be different or depending on version. Of course, if you check all return values of function calls, it recorded in your log file. However, I'm worrying about you used exact printer name by using 'EnumPrinters'.
http://msdn.microsoft.com/en-us/library/windows/desktop/dd162931(v=vs.85).aspx
I hope this helps you a little.
It seems that c++ drivers doesn't accept mongodb connection uri format.
There's no documentation on how i should create connection string, any guess?
I need to connect to a replica set with 3 servers, and set readPreference options.
Create a connection to a replica set in MongoDB C++ client
Until the problems explained in #acm's answer are resolved, I have found a workaround to the bad Connection Strings of the C++ driver. You can create a DBClientReplicaSet using a vector of hosts and ports this way:
//First create a vector of hosts
//( you can ignore port numbers if yours are default)
vector<HostAndPort> hosts;
hosts.push_back(mongo::HostAndPort("YourHost1.com:portNumber1"));
hosts.push_back(mongo::HostAndPort("YourHost2.com:portNumber2"));
hosts.push_back(mongo::HostAndPort("YourHost3.com:portNumber3"));
//Then create a Replica Set DB Client:
mongo::DBClientReplicaSet connection("YourReplicaSetName",hosts,0);
//Connect to it now:
connection.connect();
//Authenticate to the database(s) if needed
std::string errmsg;
connection.auth("DB1Name","UserForDB1","pass1",errmsg);
connection.auth("DB2Name","UserForDB2","pass2",errmsg);
Now, you can use insert, update, etc. just as you did with DBClientConnection. For a quick fix, you can replace your references to DBClientConnection with DBClientBase (which is a parent to both DBClientConnection and DBClientReplicaSet)
Last pitfall: if you are using getLastError(), you must use it with the aimed database name like this:
connection.getLastError(std::string("DBName"));
cause otherwise it will always return "command failed: must log in" as described in this JIRA ticket.
Set the read preferences for every request
You have two ways to do that:
SlaveOK option
It lets your read queries be directed to secondary servers.
It takes place in the query options, which are at the end of the parameters of DBClientReplicaSet.query(). The options are listed in Mongo's official documentation
The one you would look for is mongo::QueryOption_SlaveOk, which will allow you to have reads made on secondary instances.
This is how you should call query();
connection.query("Database.Collection",
QUERY("_id" << id),
n,
m,
BSON("SomeField" << 1),
QueryOption_SlaveOk);
where n is the number of documents to return (0 if you don't want any limit), m the number to skip (defaults to 0), the next field is your projection and the last your query option.
To use several query option, you can use bitwise or | like this :
connection.query("Database.Collection",
QUERY("_id" << id),
n,
m,
BSON("SomeField" << 1),
QueryOption_SlaveOk | QueryOption_NoCursorTimeout | QueryOption_Exhaust);
Query::readPref option
The Query object has a readPref method which sets read preferences for a special query. It should be called for each query.
You can pass different arguments for more control. They are listed here.
So here's what you should do (I did not test that one cause I can't right now but it should work just fine)
/* you should pass an array for the tags. Not sure if this is required.
Anyway, let's create an empty array using the builder. */
BSONArrayBuilder bab;
/* if any, add your tags here */
connection.query("Database.Collection",
QUERY("_id" << id).readPref(ReadPreference_SecondaryPreferred, bab.arr()),
n,
m,
BSON("SomeField" << 1),
QueryOption_NoCursorTimeout | QueryOption_Exhaust);
Note: if any readPref option is used, it should override the slaveOk option.
Hope this helped.
Please see the connection string documentation for details on the connection string format.
(code links below are to 2.2.3 files)
To use a connection string with the C++ driver, you should use the ConnectionString class. You first call the ConnectionString::parse static method with a connection string to obtain a ConnectionString object. You then call ConnectionString::connect to obtain a DBClientBase object which you can then use to send queries.
As for read preference, at the moment I do not see a way to set the read preference in the connection string for the C++ driver, which would preclude a per-connection setting.
However, the implementation of DBClientBase returned by calling ConnectionString::parse with a string that identifies a replica set will return you an instance of DBClientReplicaSet. That class honors $readPreference in queries, so you can set your read preference on a per-query basis.
Since the current C++ drivers still do not accept the standard mongodb connection URIs, I've opened a ticket:
https://jira.mongodb.org/browse/CXX-2
Please vote for it to help get this fixed.
it seems like you can set read Preference before send a read request by call "readPref" method of your Query object. I'v not found a way to set read Preference on mongo collection object yet.