What is a non-aggregated column in sql

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.

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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