Most voted "normalization" questions
Data normalization is a series of steps that follow in the design of a database, allowing consistent storage and efficient access to data in relational databases. These steps reduce data redundancy and the chances of data becoming inconsistent.
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75
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answers10585
viewsWhat is database normalization?
I was talking to some programmer friends when I heard the term "database normalization". Although I’ve heard that term a few times before, I couldn’t understand what it was about. Some doubts have…
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37
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answers13910
viewsWhat is the best way to represent an Address?
When modeling addresses in an application, naively followed the standard form when representing in the BD (i.e. separate tables for country, state, city, neighborhood etc. - joins everywhere), and…
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34
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answers8960
viewsWhen is it interesting to denormalize the database?
Is there any situation where having the database denormalized is more interesting than having it normalized? For example Normalized Pessoas Cidades | nome | cidade_id | | id | nome |…
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23
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answers4023
viewsCan it be considered a bad modeling practice to store all people (customers, employees, suppliers) in the same table?
I am trying to design a database for a small project but I am having difficulties regarding the normalization of the tables of persons (physical and legal): Client Supplier Professional I thought…
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12
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answers2560
viewsDatabase redundancies are always undesirable?
I am developing a system that keeps a record of all financial transactions occurring in a bank account (simple matches). There is a redundancy in my data model: a table saldo_conta keeps a list of…
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6
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answers1494
viewsDelete record with duplicate (Id) leaving only one occurrence
This is an old bank, dbase who was transferred to MSSQL. How to leave only one occurrence in the case of id duplicated in a table? | Id| Nome | |-----------| | 1 | JOSE | | 1 | JOSE | | 2 | MARIA |…
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6
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answers853
viewsNormalize values separated by comma for new table
The idea is to stop having the column with the values separated by comma and pass them to an intermediate table: Source table Assuming a table with the name press with the following fields: id,…
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4
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answers717
viewsNormalization of tables and relationships
I’m starting a project from scratch and in the middle of bank modeling, I had a problem. While building the models, I couldn’t do it the right way and I ended up getting confused. I have student…
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4
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answer201
viewsWhy do normalized schematics up to 3FN not have N:N relationships?
Explanation of the concept I believe that by definition a database schema is found in 3FN, when it is in 1FN,2FN and nay has transitive dependency. Transitive dependence is when an attribute NONKEY,…
database modeling software-architecture normalizationasked 6 years, 7 months ago Jonathas B. C. 883 -
4
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answers210
viewsExample of Scheme respecting the 3FN?
When studying about 3FN I came across 2 interesting examples and I wondered if when making a small change, the examples would continue to meet 3FN. Explanation about the concept of 3FN Explaining…
database modeling software-architecture normalizationasked 6 years, 7 months ago Jonathas B. C. 883 -
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answer114
viewsDOUBT About the use of SELECT and Standard Tables
I have a question as to the advantages of having standardised tables and their forms of use within a SELECT. Suppose the following tables: -------------- | tb_endereco | -------------- | id | | rua…
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3
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answers66
viewsStoring data that can be accessed outside the database itself, goes against the 1st Normal Form?
For example, I have an invoice, which I can consult in another database (but not of my property), an example would be Pagseguro. I store only the invoice identification number to be able to consult.…
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3
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answers2419
viewsPrimary key in associative table(Many for many)
Good night. I have the following question in relation N to N. Foreign keys become a primary key composed of the associative table. Correct? Does this guarantee that there is no repetition between…
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3
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answer779
viewsDatabase normalization in HR system
I am developing an HR application, in it I will have many forms in HTML that may or may not be very extensive, the employee table for example has 45 fields, some fields like company, function and…
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2
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answers40
viewsDatabase normalization with 'parent services' and 'child services'
I am modeling a database which services belong to a category (used in most cases). Currently, categories are defined in the service table itself with a 'level' flag where I say whether that record…
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2
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answers129
viewsBest way for database normalization
What would be the best way forward regarding data normalization? The system will have basically three types of "people": Agency Collaborator Client These entities have some common properties, for…
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answer203
viewsTernary relationship of entities in a relational scheme would be counter-normative, and how to do this mapping in Entity framework 6?
Taking as an example: We can abstract the relationship in several ways, one of them would be putting relation of N p/ N between project and skills needed, while another for employee and skills…
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answer76
viewsHow do I perform a normalization of curves in python?
Good afternoon everyone, I am doing an exploratory analysis of data in Python using the classic DF kc_house_data, and I came across the following problem. I would like to make some comparisons to…
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answers307
viewsHow to normalize multiple images in Matlab
I have a set of 1000 randomly generated images through the Gaussian noise, as I would to normalize them (same standard deviation and same average for all images). THANK YOU!!
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answers120
viewsHow to apply a mathematical expression to all columns of a table in SAS?
The expression will be applied to each of the 747 columns of a table/dataset. It follows the expression: (variable - variable average) / (maximum variable value - minimum variable value). Will be…
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answers951
viewsTable normalization for 2nd Normal Form
A relation is in 2FN if and only if it is in 1FN and not contains partial dependencies. From this definition I am normalizing a BD to 2FN. This BD has 2 tables, which illustrates the figure with…
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answer190
viewsNormalizing values, what am I missing?
R s are matrices of the type [120.0, 77.34999999999998, 12.639999999999974, 39.270000000000074, 62.879999999999846, 54.549999999999656, 2.400000000000313, 50.0, 50.0, 50.0, 50.0, 50.0, 50.0, 50.0,…
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answers911
viewsFields with the same name in different tables
Fields with the same name in different tables may cause conflict at the time of normalizar or make some inner join? Examples Supplier Table Field: name Field: surname Field: email Product Table…
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answer43
viewsMysql - A single entity (N:N)
Good morning guys. I’m new to database and I’m trying to understand some concepts: A single entity (N:N) A company works with projects in a horizontal way, where the person N in a project can be the…
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answer193
viewsValues that are calculated, if you store the value with the calculations in the database?
I am developing a system where a product undergoes 3 changes before reaching its final value: Individual Discount, Selling Bonus and General Discount I want to know if, I should store only the…
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answers150
viewsIs this kind of normalization feasible?
From here you will have more tables where the person will classify as, owner, customer, supplier, among others. My question is, by separating one table for Cpf and another for cnpj from the person…
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answers369
viewsPHP - Function to remove character and concatenate strings (relative URL to absolute)
Good staff! I have a small problem (problem because I don’t work much with php). I’m using a script attached to phpbb that displays the topics of a given forum on an external page, but cms returns…
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answer68
viewsIs it possible to say that the scheme is normalized in 3FN?
Explaining the Context In the internet found an example of a scheme described in this way: account(num-conta, descr-conta, launching(num-lanc, tipolanc, data-lanc, valor-lanc)). Notice that the way…
database modeling relational-model relationship normalizationasked 6 years, 7 months ago Jonathas B. C. 883 -
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answer185
viewsNormal Forms Data Modeling
I have a file excell with PRODUCT AND ORDER information. It is out of the normal forms as the information is all in one table. I’m climbing up through bulk insert this information for a database in…