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e.g.:
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the above sql is the same function as:
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Group functions
SELECT [column,] group_function(column) ... from table [WHERE condition] [GROUP BY group_by_expression] [ORDER BY column];
e.g.:
SELECT department_id, job_id, SUM(salary), COUNT(employee_id) from employees GROUP BY department_id, job_id ;
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statement_id varchar2(30),
timestamp date,
remarks varchar2(80),
operat ......
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