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digitalmars.D - How do I filter out data from mongodb in D-code

reply Anders S <anders xore.se> writes:
Hi,

I'm working on a middleware application that reads array of data 
from a POSIX pipe and insert data into the db if any position in 
the array has changed.
This is where my problem lays, in order not to duplicate data I 
want to fetch the latest data/document in the array of documents.
I'm using MS Code and dub to code and compile.

This is the code:
Collection ct = mongo.boxweb.celltab;
int i = 1;
for(;i < 10; i++ ){
    auto cell = 
ct.find({"number":i}).sort({_id:-1}).limit(2).pretty();
    if (<data from pipe[i].pos1 == cell.pos1) then do some 
insert...

    i++;
....
Where "number" is the document nr in the array

I get these errors
source/app.d(166,54): Error: found : when expecting ; following 
statement
source/app.d(166,56): Error: found } when expecting ; following 
statement
source/app.d(166,57): Error: found ) instead of statement
dmd failed with exit code 1.

Any ideas?
Isn't there a way to markup code in the forum message to separate 
from the bodytext?

/anders
Oct 10 2017
next sibling parent Anders S <anders xore.se> writes:
On Tuesday, 10 October 2017 at 09:43:10 UTC, Anders S wrote:

 I'm working on a middleware application that reads array of 
 data from a POSIX pipe and insert data into the db if any 
 position in the array has changed.
 This is where my problem lays, in order not to duplicate data I 
 want to fetch the latest data/document in the array of 
 documents.


To clarify,

This is where my problem lays, in order not to duplicate data I 
want to fetch the >latest data/document in the array of 
documents.


refers to latest inserted data/document in the mongodb 
collection. Also that the insert of document that changed include 
a timestamp like this
dateAdded: new Date()
Oct 10 2017
prev sibling parent Eduard Staniloiu <edi33416 gmail.com> writes:
On Tuesday, 10 October 2017 at 09:43:10 UTC, Anders S wrote:

 Hi,

 I'm working on a middleware application that reads array of 
 data from a POSIX pipe and insert data into the db if any 
 position in the array has changed.
 This is where my problem lays, in order not to duplicate data I 
 want to fetch the latest data/document in the array of 
 documents.
 I'm using MS Code and dub to code and compile.

 This is the code:
 Collection ct = mongo.boxweb.celltab;
 int i = 1;
 for(;i < 10; i++ ){
    auto cell = 
 ct.find({"number":i}).sort({_id:-1}).limit(2).pretty();
    if (<data from pipe[i].pos1 == cell.pos1) then do some 
 insert...

    i++;
 ....
 Where "number" is the document nr in the array

 I get these errors
 source/app.d(166,54): Error: found : when expecting ; following 
 statement
 source/app.d(166,56): Error: found } when expecting ; following 
 statement
 source/app.d(166,57): Error: found ) instead of statement
 dmd failed with exit code 1.

 Any ideas?
 Isn't there a way to markup code in the forum message to 
 separate from the bodytext?

 /anders



Hello,

I haven't used mongo and D together, but by looking at [0] and 
[1] I can see that mondo is using Bson, which, as far as I can 
tell takes an associative array.

I'm guessing you need to replace the JS dictionary sintax { k: v 
} with the AA one [ k: v ].

I haven't been able to try this out as I am on my phone. Also, 
this might be more suited for the Learn thread.

Regarding the code markup, as far as I know, we don't have this.

Hope this helps,
Eduard

[0] - https://code.dlang.org/packages/mondo
[1] - http://vibed.org/api/vibe.data.bson/
Oct 10 2017