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:
| Features | Aggregation column | Non-aggregation column |
|---|---|---|
| Number, date, string | Various data types | |
| Applicable (such as SUM, COUNT) | Not applicable | |
| Aggregation value of multiple records | Single value of each record | |
| Statistical analysis, trend identification | Identification, filtering, sorting |
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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