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Explain group By clause in SQL?
Group By clause in SQL: The GROUP BY clause can be used in a SELECT statement to collect data across multiple records and group the results through one or more columns.
The syntax for the GROUP BY clause is:
SELECT column1, column2, ... column_n, aggregate_function (expression)FROM tablesWHERE predicatesGROUP BY column1, column2, ... column_n; aggregate_function could be a function like as SUM, COUNT, MIN, or MAX.
Describe the statement in SQL which allows to change the definition of a table? In SQL Alter statement is used to allow the changes the definition of a table.
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