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Topic: How to consider any amount of attributes at essence

Now I am engaged in designing at level  and logicians. A motor car park DB. At HARDWARE Mark by default 3 technical characteristics, but it is necessary to make so that it was possible to consider any amount of technical characteristics. I reflect so: to create separate essence the Technical characteristic and in it key attribute - its name. But... Something is not went. How to achieve the necessary result? Help to understand, please.
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Re: How to consider any amount of attributes at essence

Deft_Cat, EAV , but can for yours  quite fits  from set Document-oriented database ... If MS SQL it is basic, implement EAV or use types XML/JSON

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Re: How to consider any amount of attributes at essence

buser, thanks for councils! Small specification: how to show it graphically in ERWin DM? I want to understand, how it will be organized at logic level.

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Re: How to consider any amount of attributes at essence

Deft_Cat wrote:

buser, thanks for councils! Small specification: how to show it graphically in ERWin DM? I want to understand, how it will be organized at logic level.

Get the table "Technical characteristics of mark of the HARDWARE", in it two columns in the form of links to other 2 reference manuals - Mark of the HARDWARE and Technical characteristics.
Links from the table in reference manuals - the post name - the link to the reference manual of posts is similar as in employees. Only here not one link, and two. All.
The moderator: the Subject is transferred from a forum "Microsoft SQL Server".

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Re: How to consider any amount of attributes at essence

Andy_OLAP,
As a result it turns out that the label "Technical characteristics of mark of the HARDWARE" in Excel (for the subsequent import to a SQL Server) will look as follows (further, if needed, it will be possible to add characteristics, adding ++). I correctly understood your council? (Red - primary key)
And to produce, for example, all available characteristics of BMW E5 (value titles  , it is pure for an example) Connection it will be necessary by means of operation to make?
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Re: How to consider any amount of attributes at essence

Deft_Cat wrote:

Andy_OLAP,
As a result it turns out that the label "Technical characteristics of mark of the HARDWARE" in Excel (for the subsequent import to a SQL Server) will look as follows

Yes, but not absolutely. In the report table there will be Name from the reference manual, in the table of technical characteristics 2 columns ID. Otherwise after renaming of characteristic ID=234, Name = "Krosnyj" on "Red" is necessary to you  the table and in all  text "Krosnyj" to change on "Red". And if will be only ID - so it so 234 and remains.
Just in case specified this nuance, whether it is not enough.

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Re: How to consider any amount of attributes at essence

Andy_OLAP, and where to store values of characteristics if in the table "Technical characteristics of mark of the HARDWARE" will be only 2 ID? I do not understand here this moment, unfortunately...

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Re: How to consider any amount of attributes at essence

Deft_Cat wrote:

Andy_OLAP and where to store values of characteristics if in the table "Technical characteristics of mark of the HARDWARE" will be only 2 ID? I do not understand here this moment, unfortunately...

In the reference manual which you already created - Technical characteristics. ID=1 engine volume, ID=2 primary color, ID=3 the full drive, ID=4 a front drive, and so on.
Only technical characteristics concern the car, instead of to mark. Here there is a mark . Machines in the core the red. But what it concerns the specific car? Or mark of 1.6 liters, and on the car delivered the engine 1.8, well and what the account gives, what the technical characteristics of mark of the HARDWARE for the given car returns 1.6? To compare  a variant with specific for the car?
I would get the more general reference manual "car Technical characteristics", there both color, and engine volume and so on. And "technical characteristics of mark of the HARDWARE" is a link on ID marks and the link on ID total characteristics which happen generally at cars.

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Re: How to consider any amount of attributes at essence

;
For example, I will place in the table of Transportnoe_sredstvo of 3 characteristics, either 5, or 7, - and they will be not key attributes for the given table. But such that it is necessary to make a condition so that any amount of characteristics was considered. Hence, characteristics should be added somehow when it it is required. If I do not understand something, and you precisely see resolution specify, please smile

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Re: How to consider any amount of attributes at essence

On a subject the real decision already  was resulted. Time.
It is necessary only two tables:
1. The reference manual of attributes
2. The table of a binding of value of attribute to essence, i.e. key set and values.
(Profit)

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Re: How to consider any amount of attributes at essence

LSV;
So here the situation is worse. "At HARDWARE Mark by default 3 technical characteristics, but it is necessary to make so" - basis of a motor car park. On routes are exposed either gazelles, or the big buses. The author of a subject thinks that creates record "Gazelle" as HARDWARE mark, in it registers capacity of conditionally 15 persons, record "Pazik" as HARDWARE mark, in it registers capacity of conditionally 25 persons, and further from the program will select from the reference manual of attributes such as "capacity", hammer in 17 persons (on the average on a new route) and see that it is possible to start up on it , instead of .
Here is not present. Similar characteristics are a binding to the specific car.
The author of a subject - further for you the abstract speculation.
At me it is admissible mark "" - primary color red, the main capacity 2+2. Well and - my mechanics altered in a pickup, there were 2 persons a maximum, plus was recoloured in the yellow. Well also what to me from record under the technical characteristic of mark of the HARDWARE?
Or in days between checkup. Well, there are at a certain abstract gazelle the conditional 10 days. But there are gazelles of conditionally release of 2015 for whom kol-in days 10, and happens conditionally 2017, for which in days 7 (it is necessary to check is more often, at factory spoiled quality of production). And further that - to get in HARDWARE mark it is partite "gazelles of release 2015" and "gazelles of release 2017"?
Think, what for to you to fasten technical characteristics to HARDWARE mark. Whether there will be it a rake which then painfully strike...

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Re: How to consider any amount of attributes at essence

[quote =] So here the situation is worse.

It is possible to register not to the HARDWARE card, and to HARDWARE group (: passenger to 12, passenger to 25, cargo etc.).
As a variant, it is possible to make both there and there that at creation of a new card of the HARDWARE, in it ready attributes from group were copied.
Then at . The specific card can be edited.