| slovo | definícia |
normalisation
(encz) | normalisation,normalizace n: Zdeněk Brož |
normalisation
(wn) | normalisation
n 1: the imposition of standards or regulations; "a committee
was appointed to recommend terminological standardization"
[syn: standardization, standardisation,
normalization, normalisation] |
normalisation
(foldoc) | normalisation
normalised
unnormalised
1. A transformation applied uniformly to
each element in a set of data so that the set has some
specific statistical property. For example, monthly
measurements of the rainfall in London might be normalised by
dividing each one by the total for the year to give a profile
of rainfall throughout the year.
2. Representation of a floating-point number
so that its mantissa's left-most digit is non-zero. If the
leftmost fraction digit are zeros, the number is said to be
unnormalised. Unnormalised numbers are normalised by shifting
the fraction left, one digit at a time, until the leftmost
digit is nonzero and reducing the exponent by the number of
shifts.
3. database normalisation.
(1998-04-15)
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| | podobné slovo | definícia |
renormalisation
(encz) | renormalisation,renormalizace n: Zdeněk Brož |
i see a great need organisation internationale de normalisation
(czen) | I See A Great Need Organisation Internationale de
Normalisation,ISAGN[zkr.] |
comité européen de normalisation
(foldoc) | European Committee for Standardization
CEN
Comité Européen de Normalisation
(Conseil Européen pour la Normalisation, CEN) One of three European
Standardization Organizations
(together with CENELEC and ETSI) that are recognized by the
European Union and the European
Free Trade Association (EFTA) as being responsible for voluntary
standards at European level.
Home (https://www.cencenelec.eu).
(2022-03-05)
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database normalisation
(foldoc) | database normalisation
1NF
2NF
3NF
4NF
5NF
Codd's First Normal Form
fifth normal form
first normal form
fourth normal form
second normal form
third normal form
A series of steps followed to obtain a database
design that allows for efficient access and storage of data
in a relational database. These steps reduce data
redundancy and the chances of data becoming inconsistent.
A table in a relational database is said to be in normal
form if it satisfies certain constraints. Codd's original
work defined three such forms but there are now five generally
accepted steps of normalisation. The output of the first step
is called First Normal Form (1NF), the output of the second
step is Second Normal Form (2NF), etc.
First Normal Form eliminates repeating groups by putting
each value of a multi-valued attribute into a new row.
Second Normal Form eliminates functional dependencies on a
partial key by putting the fields in a separate table from
those that are dependent on the whole key.
Third Normal Form eliminates functional dependencies on
non-key fields by putting them in a separate table. At this
stage, all non-key fields are dependent on the key, the whole
key and nothing but the key.
Fourth Normal Form separates independent multi-valued facts
stored in one table into separate tables.
Fifth Normal Form breaks out data redundancy that is not
covered by any of the previous normal forms.
(http://bkent.net/Doc/simple5.htm).
[What about non-relational databases?]
(2005-07-28)
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head normalisation theorem
(foldoc) | head normalisation theorem
Under the typed lambda-calculus, beta/delta reduction of the
left-most redex (normal order reduction) is guaranteed to
terminate with a head normal form if one exists. See also
Church-Rosser theorem.
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