why is batching of aggregate by weight is preferable than batching by volume
Usually there is no use of nulls but in some case there might be some use. Like consider a case a persons address has been changed but the new address is not known. In this case it is prefer to left the field null instead of wrong address.
1. special requirements for its use in SQL joins. 2. special handling required by aggregate functions and SQL grouping operators
Statistics is a mathematical science pertaining to the collection, analysis, interpretation or explanation, and presentation of data.It also provides tools for prediction and forecasting based on data. Statistical methods can be used to summarize or describe a collection of data. To create statistical reports aggregate are used.Aggregate functions compute a single result value from a set of input values.
A data warehouse functions as a repository for all the data held by an organisation. The main functions are to reduce cost of data storage, facilitate data mining, and facilitate ability to back up data at an organisational level.
Nulls can significantly affect aggregate functions in SQL and other data analysis contexts. For example, when calculating averages, null values are typically ignored, which can lead to skewed results if a substantial number of records contain nulls. Similarly, functions like COUNT only consider non-null entries, potentially underreporting the number of entries in a dataset. As a result, it's essential to handle nulls appropriately to ensure accurate calculations and analyses.
When using aggregate functions in a SQL SELECT statement, restrictions often include the requirement that any non-aggregated columns in the SELECT list must be included in the GROUP BY clause. Additionally, aggregate functions will ignore NULL values, meaning that NULLs do not contribute to the calculated results, such as averages or counts, which can affect the outcome of the aggregation if NULLs are present. For instance, COUNT will only count non-NULL entries, while SUM will exclude NULLs from its total.
FALSE
Yes, they are aggregate functions. They are also statistical functions.
nothing
The interest rate does affect aggregate demand. As the interest rate falls, aggregate demand increases and vice-versa.
aggregate functions.
aggregate functions
Sigma
Zero
Classical Aggregate Supply function is vertical whereas the Keynesian Aggregate Supply function is positively sloped.
Aggregate functions: COUNT, SUM, MIN, MAX, AVG NOTE: It can be used only in the SELECT list and in the HAVING clause. Using it anywhere else will be incorrect; also you cannot nest aggregate functions.