I need to generate ids with a convention, for example:
Instead of getting: "538cd180e381f20d1c1cd2a2"
I would like to have an ID like this one: "p38cd180e381f20d1c1cd2a2"
So what I want is that my IDs start with a consonant letter.
Does anyone know how to accomplish that within the driver, I mean, getting that behaviour on "new mongo.ObjectId()"?
Thanks in advance.
You can use the following, to get the id starting with a consonant
db.collection.insert({"_id":"p"+new ObjectId()})
you can use any other string in place of "p" and the string will append to the start of the id generated by mongodb.
Short answer: Sorry, no standard way available to achieve this as of now.
Detailed answer and workaround: MongoDB or driver generated ids are a combination of Creation Time (as timestamp), Increment value for next id, Machine on which the id is generated and the process id of the process which generated this document id. All this info is available in the generated id and can be extracted back. For now, this is what you have been given and there is no support for generating your own custom id from the driver's algorithm.
If you want to customize your id generation and be able to make use of these properties, then you can embed all this info that MongoDB uses for id generation and add this information to your document itself. By doing that you will be able to reproduce the information that MongoDB generates from the id. And while inserting the document to MongoDB, you can give your docs a customized id which agrees with your requirements.
So if you later on want to make comparisons based on creation time or maybe the machine, you can do that from the information that was added to the docs themselves.
Use the code: db.collection.insert({"customId":"p"+new ObjectId()}). And let your code use this customId.
Related
I have a dynamo script that exports schedules out of Revit. It uses a bit of Python also, (not relevant to this question, but I thought I would just include it all).
It all works great, but I notice if certain schedules get deleted from Revit, it could change the "Index" number of the schedules I need to export. I would like to use the schedule name instead of the dynamo index number, as this will help me maintain the connection without checking if it's exporting the correct schedule. Is this possible?
From the pure Revit API point of view I can only answer that yes, this is possible. You are calling the ViewSchedule.Export method. The ViewSchedule element can indeed be retrieved from the Revit database by name using a filtered element collection.
Here is the final solution that works well. Using the "==" node and "List.FilterByBoolMask" node I was able to filter down to just what's in the String. Now I can set the string node to be an input for the dynamo player and user just needs to input the exact name of their schedule. Thank you Michael Kilkelly from ArchSmarter for this helpful video.
How to Dynamo: Filter List by Element Name
I would like to get all the docs in couchDb updated in a specific time range.
I'm using the below API but I don't get any result.
/_all_docs?startkey="2019-01-01T00:00:00Z"&endkey="2020-01-01T00:00:00Z"
Any suggestions are welcome.
Andrea
_all_docs's key is the document ID, not timestamp. For your query to be useful, you'll need to create a custom view based on a timestamp (and ensure the timestamp is updated by your code).
In past with my PHP / Rails - MYSQL apps I've used the unique ID of a table record to keep track of a record in an html file.
So I'd keep track of how to delete a record shown like this (15 being the ID of the record):
Delete this record
So now I'm using MongoDB. I've tried the same method but the objectID ._id attribute seems to be a loooong byte string that I can't use conveniently.
What's the most sensible way of binding a link in the view to a record (for deletion, or other purposes or whatever)?
If the answer is to create a new id that's unique for each document in the collection, then what's the best way to generate those unique id's?
Thank you.
You could use a counter instead of the ObjectID
But this could create a problem when inserting a new document after you deleted a previous one.
See this blog post for more detail info on Sequential unique identifiers with Node.js and MongoDB.
Or you could use the timestamp part of the ObjectID:
objectId.getTimestamp().toString()
See the node objectid docs
How can I get last created document in couchdb? Maybe some how I can use _changes feature of couchdb? But documentation says, that I only can get list of document, ordered by first created document, ant there is no way to change order.
So how can I get last created document?
You can get the changes feed in descending order as it's also a view.
GET /dbname/_changes?descending=true
You can use limit= as well, so;
GET /dbname/_changes?descending=true&limit=1
will give the latest update.
Your only surefire way to get the last created document is to include a timestamp (created_at or something) with your document. From there, you just need a simple view to output all the docs by their creation date.
I was going to suggest using the last_seq information from the database, but the sequence number changes with every single write, and replication also complicates the matter further.
I am doing a workflow for a document library. I put a OnWorkflowItemChanged, and I want to get the value of the column which is changed. I use the workflowProperties.Item["name"] and use the afterProperties. But when I use the workflowProperties.Item["column name"], I still got the original value. When I use the afterProperties, it's NULL.
Then I make another workflow that is the same as above for a list. I can use the workflowProperties.Item["column name"] to get the new value in OnWorkflowItemChanged.
Has anyone come across this problem before? Can you give me some help?
The question seems to mix up Item with ExtendedProperties. As to why a difference is seen on a List/Document Lib, it might have something to do with versionining or perhaps the internal serialization is different. Anyway, some of my experience is outline below. I hope it may be of use:
Use the GUID (as a Guid object, not a string) to access the Before / After ExtendedProperties field. Using the Display Name in the ExtendedProperties will not work. The documentation on it is wrong. You can use SPList.Fields to go from Display Name to Column ID (Guid).
I bind all "Before" to MyWhatever_PreviousProperties and all "After" to MyWhatever_Properties, only accessing MyWhatever_[Previous]Properties after the appropriate event(s)).