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Questions tagged [mapping]

Corresponding every element of a given set to a unique element of another set or it may refer to a process of creating data element mappings between two distinct data models (objects)

In this context, mapping refers to the process of creating data element mappings between two distinct data models (objects).

When it refers to mapping in data integration, it is a set of source and target definitions linked by the transformation objects that define the rules for data transformation. Mappings represent the data flow between sources and targets.

Data mapping is typically used as a first step for a wide variety of data integration tasks such as:

  1. Data transformation or data mediation between a data source and a destination

  2. Identification of data relationships as part of data lineage analysis

  3. Replication of data between two entities with different key-value assignments

  4. Discovery of hidden sensitive data such as the last four digits social security number hidden in another user id as part of a data masking or de-identification project

  5. Consolidation of multiple databases into a single data base and identifying redundant columns of data for consolidation or elimination.

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What is the difference between the remap, noremap, nnoremap and vnoremap mapping commands in Vim?

What is the difference between the remap, noremap, nnoremap and vnoremap mapping commands in Vim?
Chetan
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Reverse / invert a dictionary mapping

Given a dictionary like so: my_map = {'a': 1, 'b': 2} How can one invert this map to get: inv_map = {1: 'a', 2: 'b'}
Brian M. Hunt
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Server.MapPath("."), Server.MapPath("~"), Server.MapPath(@"\"), Server.MapPath("/"). What is the difference?

Can anyone explain the difference between Server.MapPath("."), Server.MapPath("~"), Server.MapPath(@"\") and Server.MapPath("/")?
Manu
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What is the ideal data type to use when storing latitude / longitude in a MySQL database?

Bearing in mind that I'll be performing calculations on lat / long pairs, what datatype is best suited for use with a MySQL database?
Codebeef
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Mapping two integers to one, in a unique and deterministic way

Imagine two positive integers A and B. I want to combine these two into a single integer C. There can be no other integers D and E which combine to C. So combining them with the addition operator doesn't work. Eg 30 + 10 = 40 = 40 + 0 = 39 +…
harm
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any tool for java object to object mapping?

I am trying to convert DO to DTO using java and looking for automated tool before start writing my own. I just wanted to know if there any free tool available for the same.
ravinikam
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What is the best way to implement nested dictionaries?

I have a data structure which essentially amounts to a nested dictionary. Let's say it looks like this: {'new jersey': {'mercer county': {'plumbers': 3, 'programmers': 81}, 'middlesex county':…
YGA
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When do you use map vs flatMap in RxJava?

When do you use map vs flatMap in RxJava? Say, for example, we want to map Files containing JSON into Strings that contain the JSON-- Using map, we have to deal with the Exception somehow. But how?: Observable.from(jsonFile).map(new Func1
Christopher Perry
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How do you create nested dict in Python?

I have 2 CSV files: 'Data' and 'Mapping': 'Mapping' file has 4 columns: Device_Name, GDN, Device_Type, and Device_OS. All four columns are populated. 'Data' file has these same columns, with Device_Name column populated and the other three columns…
atams
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What is the "owning side" in an ORM mapping?

What exactly does the owning side mean? What is an explanation with some mapping examples (one to many, one to one, many to one)? The following text is an excerpt from the description of @OneToOne in Java EE 6 documentation. You can see the concept…
Just a learner
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Mapping many-to-many association table with extra column(s)

My database contains 3 tables: User and Service entities have many-to-many relationship and are joined with the SERVICE_USER table as follows: USERS - SERVICE_USER - SERVICES SERVICE_USER table contains additional BLOCKED column. What is the best…
archie_by
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No mapping found for field in order to sort on in ElasticSearch

Elasticsearch throws a SearchParseException while parsing query if there are some documents found not containing field used in sort criteria. SearchParseException: Parse Failure [No mapping found for [price] in order to sort on] How can I…
Yadu
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Entity framework code-first null foreign key

I have a User < Country model. A user belongs to a country, but may not belong to any (null foreign key). How do I set this up? When I try to insert a user with a null country, it tells me that it cannot be null. The model is as follows: public…
Shawn Mclean
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Converting from longitude\latitude to Cartesian coordinates

I have some earth-centered coordinate points given as latitude and longitude (WGS-84). How can i convert them to Cartesian coordinates (x,y,z) with the origin at the center of the earth?
daphshez
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Math - mapping numbers

How do I map numbers, linearly, between a and b to go between c and d. That is, I want numbers between 2 and 6 to map to numbers between 10 and 20... but I need the generalized case. My brain is fried.
Sam
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