Book - Chapter 11 In Database Analytics Flashcards
What does in database analytics mean
Describe the processing of data within its repository
What are the three advantages to using tables
Disk storage saving. Changes and corrections are easily made. Products can be added to the database prior to any orders being placed.
What is the process of reducing duplications
Normalisation
What is the select function
Specifies the table columns to be displayed
What is the from function
Specifies the name of the table to be queried
What is the where function
Specifies the criterion or filter to be applied
What is the joint function
Specify the relationships between the multiple tables
What is an inner join
Returns rows from the two tables where the ON criteria is met
What is the order by function
Sorts of records
What is a right outer join function
All rows on the table on the right hand side of the join should be returned regardless of whether there is matching
What is the union all function
Mergence the results of the two select statements regardless of any duplicate records appearing in both select statements
What is the union function
It is the same as the union all by which it emerges the results of two select statements but it eliminates any duplicates
What is the intersect function
Determines any identical records that are returned by two select statements.
What is the sub query
Also known as a nested query. It is an SQL query with in a query
What is the roll up function
Provides of subtotal
What is the cube function
Providing subtotals for each column specified
In regular expressions what does this symbol mean
^
Looks for matches at the beginning of the string
In regular expressions what does this symbol mean
|
Matches item A or B
In regular expressions what does this symbol mean
$
Looks for matches at the end of the string
In regular expressions what does this symbol mean
*
Matches preceding item 0 or more times
What is a rank function
Can be used to order a set of rose based on some attribute
What does EWMA stand for
Exponentially weighted moving average
What is madlib
And open source library for scalable in database analytics
What does madlib stand for
Magnetic agile deep
What is the data lake
Represents an environment that Kalex and stores large volumes of structured and unstructured data sets
