What is cardinality in Databases? - Stack Overflow
May 16, 2012 · Could somebody explain to me, with the help of examples, what is cardinality in databases?
What is the definition of cardinality in SQL - Stack Overflow
Aug 28, 2014 · High-cardinality - many tuples, low-cardinality - few tuples. While the Wikipedia article on Cardinality (SQL statements), defines it as follows: Cardinality refers to the …
database - Multiplicity vs Cardinality - Stack Overflow
May 7, 2022 · When talking about data models and databases, the term Cardinality is often used to describe the number of allowed elements in a given set. UML often refers to the same …
How much cardinality can I have in my prometheus metrics?
Nov 18, 2024 · In my experience a prometheus server can easily handle in the order of 1000 servers sending 1000 metrics. That's about a million active time series. A prometheus server …
database - Trying to understand cardinality in an entity …
Dec 23, 2015 · The cardinality at the end of a line tells you for a given entity instance how many relationship instances/rows it can appear in. If a given instance/value doesn't have to appear …
What is the meaning of Cost, Cardinality and Bytes in Explain Plan?
Feb 11, 2018 · Cardinality is the number of rows the optimizer guesses will be processed for a plan step. If the stats are old, missing, or incomplete - then this can be wildly wrong. You want …
sql - TableCardinality - Stack Overflow
Aug 25, 2010 · Cardinality is the number of UNIQUE values for a given table / column (so it's not surprising that is equal to the number of entries in the primary key index as that index is most …
Difference between one-to-many and many-to-one relationship
Jan 5, 2011 · Cardinality Cardinality is declared first in the data model, which means Logical and Physical (the intent), and then in the implementation (the intent realised). One to zero-to-many …
indexing - What is cardinality in MySQL? - Stack Overflow
Apr 2, 2010 · What is cardinality in MySQL? Please explain in simple, non-technical language. If a index detail of any table displays the cardinality of a field say group_id as 11, then what does …
Which column to put first in index? Higher or lower cardinality?
Sep 7, 2012 · For example, if I have a table with a city and a state column, what is the best way to use the index? Obviously city will have the highest cardinality, so should I put that column first …