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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Rename columns in Pandas based on a dictionary

I have a pandas DataFrame and I would like to rename the columns based on another DataFrame that I plan to use as dictionary. For example, the first DataFrame is: AAA BBB CCC DDD index 1 1 2 3 4 2 5 …
km1234
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How to map a latitude/longitude to a distorted map?

I have a bunch of latitude/longitude pairs that map to known x/y coordinates on a (geographically distorted) map. Then I have one more latitude/longitude pair. I want to plot it on the map as best is possible. How do I go about doing this? At first…
Adam Ernst
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Incompatible Data Reader Exception From EF Mapped Objects

I am using Entity Framework and have updated a table and its stored procedure but I'm getting the following error when the stored procedure is called. The data reader is incompatible with the specified 'FormValueModel.Valuation'. A member of the…
Pomster
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Mapping deeply hierarchical objects to custom classes using knockout mapping plugin

Using the knockout mapping plugin ( http://knockoutjs.com/documentation/plugins-mapping.html ) can you map a deeply hierachical object? If I have an object with multiple levels: var data = { name: 'Graham', children: [ { …
Mark Robinson
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Entity Framework 4.1 code first approach: how to define length of properties

As the title implies: how is it possible to tell Entity Framework 4.1 in code first approach, that i do want some properties (in particular of type string) to have a length of 256, or nvarchar(max), or... So if this is for example my model public…
Savvas Sopiadis
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Hibernate XML Mapping: Lazy False or Fetch Select?

I have a simple question. I found this Hibernate config on our project:
chris
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Map Routing, a la Google Maps?

I've always been intrigued by Map Routing, but I've never found any good introductory (or even advanced!) level tutorials on it. Does anybody have any pointers, hints, etc? Update: I'm primarily looking for pointers as to how a map system is…
Mark Harrison
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Good examples of MapServer / OpenLayers

I want to convince some clients to use MapServer and OpenLayers. Please can anyone suggest attractive websites to show off the possiblities! The clients will be impressed by: A density map (otherwise known as a heat map, colour-shaded grid…
MarkJ
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Mapping A Sphere To A Cube

There is a special way of mapping a cube to a sphere described here: http://mathproofs.blogspot.com/2005/07/mapping-cube-to-sphere.html It is not your basic "normalize the point and you're done" approach and gives a much more evenly spaced…
petrocket
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What’s the purpose of mmap memory protection PROT_NONE

I was reading the documentation of mmap and fell upon this line: PROT_NONE Pages may not be accessed. Is there any use to map a file to memory but never access it?
qdii
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Read embedded object in Jackson

I'm trying to read a legacy JSON code using Jackson 2.0-RC3, however I'm stuck with an "embedded" object. Given a following JSON: { "title": "Hello world!", "date": "2012-02-02 12:23:34". "author": "username", "author_avatar":…
Crozin
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Migrate field type from text to keyword on Elasticsearch

When I want to change the type of a field from text to keyword with this commande : PUT indexStat/_mapping/StatCateg { "StatCateg":{ "properties": { "nom_categorie": { "type":"keyword","index": true } } } } I have…
C.Rouillon
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vim remapping the hjkl

I am trying to map the letter hjkl to jkl in my .vimrc file so that I can have my fingers the way they always are on the keyboard, while writing in vim. The problem is that as I map k to l, it jumps into the l to ;. so k becomes the same as ;. The…
john-jones
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Does the JPA specification allow references to non-primary key columns?

Does the JPA specification allow simple references to non-primary key columns? I have a simple alternative/natural key (UNIQUE, NOT NULL) column iso_code on my Countries table which I'd like to use in a reference, but Eclipse's Dali shows a…
Kawu
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Store Json field as String in Elastic search?

I am trying to index a json field in elastic search, I have given it external mapping that this field should be treated as string and not json, also indexing is not required for it, so no need to analyze it. The mapping for this is…
NIlesh Sharma
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