what is Cardinality and Collation means ?

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madan koshti
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what is Cardinality and Collation means ?

Post by madan koshti »

what is mean by mysql table Cardinality and Collation ?
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Eran
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Re: what is Cardinality and Collation means ?

Post by Eran »

A collation is a set of rules for comparing characters in a character set. http://dev.mysql.com/doc/refman/5.0/en/ ... neral.html
Cardinality is a measure of uniqueness for data in a row. It represents how different the rows in your table are from each other. http://en.wikipedia.org/wiki/Cardinalit ... tatements)
madan koshti
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Re: what is Cardinality and Collation means ?

Post by madan koshti »

pytrin wrote:A collation is a set of rules for comparing characters in a character set. http://dev.mysql.com/doc/refman/5.0/en/ ... neral.html
Cardinality is a measure of uniqueness for data in a row. It represents how different the rows in your table are from each other. http://en.wikipedia.org/wiki/Cardinalit ... tatements)
What is mean by cardinality in integer value ?
e.g:
cardinality 5
cardinality 7
cardinality 10 etc... ?
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Eran
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Re: what is Cardinality and Collation means ?

Post by Eran »

It means how many unique rows you have in your table (according to the primary key)
madan koshti
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Re: what is Cardinality and Collation means ?

Post by madan koshti »

pytrin wrote:It means how many unique rows you have in your table (according to the primary key)

Hey Thanks..............
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