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What is a non-aggregated column in sql

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May 01, 2024 pm 10:51 PM

aggregate function

Non-aggregated columns in SQL are columns that store single record values and will not be processed by aggregate functions. These columns contain unique values for each record and are used to identify, categorize, or filter the data.

What is a non-aggregated column in sql

Non-aggregated columns

In SQL, a non-aggregated column refers to a column that stores the value of a single record in a table. These values are not processed by aggregate functions (such as SUM, COUNT, or AVG), but are stored and retrieved as individual data points.

Characteristics of non-aggregated columns:

Contains the unique value of each record
will not be operated by aggregate functions
Usually used to identify, classify or filter data

The difference between aggregated columns and non-aggregated columns:

##Data typeNumber, date, string Various data types##Aggregation functionsValueUsage scenarios

Features	Aggregation column	Non-aggregation column

Applicable (such as SUM, COUNT)	Not applicable
Aggregation value of multiple records	Single value of each record
Statistical analysis, trend identification	Identification, filtering, sorting

Examples of non-aggregated columns:

Order ID in the orders table

Customer name in the customer table
Product name in the product table
These columns store the A specific value and will not be used in aggregate calculations.

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