I am about to start to play around with the Bitcoin open source, source code, and got introduced to a new term: a Blockchain database.

What technologies are needed for this? Is this NO-SQL?

Thanks.

I am using php and mongoDb. I am new to mongoDb, but fine with php.  In my mongoDb database I have a  collection called 'users' with a number of fields such as firstname, lastname etc. There are a number of users.


I also have a field/collection in some users called web_links which contains an array.
ie: within my users document:
{
    "_id" : ObjectId("587af11ec09cf31a1955ed92"),
    "username" : "mike",
    "firstname" : "Mike",
    "lastname" : "Tester",
    "email" : "mike@test.com",
    "web_links" : [
        {
            "name" : "google",
            "link" : "https://google.com",
            "status" : "1",
            "added" : ISODate("1970-01-18T08:00:57.600Z")
        },
        {
            "name" : "yahoo",
            "link" : "https://yahoo.com",
            "status" : "1",
            "added" : ISODate("1970-01-18T08:00:57.600Z")
        }
    ]
}

I am trying to firstly update the status of an array item.
I have got as far as this ->

$name = 'google';
$newstatus = '0';

$this->database->users->updateOne(['_id'=>new MongoDB\BSON\ObjectId($userid)],['web_links.name'=>$name],['$set'=>['web_links.$.status'=>$newstatus]]);

This is returning the following error via firebug:
Uncaught exception 'MongoDB\Exception\InvalidArgumentException' with message 'First
 key in $update argument is not an update operator'.

I have tried to change $set to $push, but that is not the answer.

I would be very grateful for assistance …

Hi there,

I have a mongo aggregation query that works fine in the mongo shell (and robomongo) but I can not work out how to translate this into a PHP query.

I am using PHP 5.6 with the latest mongo class (MongoDB\Driver\Query).  The mongo query looks like this:

db.products.aggregate(
   [
     {$match: {
             vendor_name : "vendor8",
             distributor_id : 8
         }
     },    
     { $sort: { 
         cw_product_code: 1, download_Date: 1 
         } 
     },
     { $group:
         {
           _id: "$cw_product_id",
           lastDownloadDate: { $last: "$download_Date" },
         }
     }        
   ],
     {allowDiskUse: true}     
)

Select all Open in new window

Any help to point me in the right direction would be appreciated.

Hi Experts,

I have a database that did grow monthly the following in MB
Size
3330
3383
3426
3468
3523
3602
3686
3759
What is the way to calculate the expected growth for the next few months?

Hi Experts,

We have SQL Express 2005 and I realized our data file is almost reaching the limit (4GB).
Now my question is, how can I shrink the size of the file in order to prolong the need to upgrade (FE/BE)?

Also I see one table that has about 200 MB used for data and 450 MB for indexes, is that acceptable?
How can I see what indexes are not being used so frequent and can be dropped (for a particular table or in general)?

PS. Our front end app is an Access ADP and then therefore I don't see how the database can be split.

Thanks in advance.

Hi I have a colleague who has a SQL Script that she runs in Crystal Reports.  I need this similar script to run on our AIX box for a certain program.  It runs fine in Crystal, but it just hangs on our IBX AIX box.

It has like 14 SELECT Statements.  Is there a way I can step through this script in SQL, like a debug tool, so I can see why it is running a long time or failing without me knowing?  I wish there was a log file or something?  Is there??

Thanks in advance for help!