SQL Interview Questions #42: What is "Aggregation" in SQL?

SQL code copied to buffer

Task 42:

Mark all correct statements about aggregation in relational databases.

An aggregate is a summary statistic computed over a group of data - such as totals, averages, counts, minimums, maximums, or string concatenations.

Aggregation changes the level of detail (granularity) of a dataset, transforming atomic, row-level data into high-level metrics.

Aggregation possible only for numbers

Mark all correct answers and click the "Check!" button

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