Difference between revisions of "GROUP BY"
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GROUP BY SALES_DATE, PRODUCT_ID | GROUP BY SALES_DATE, PRODUCT_ID | ||
HAVING SUM(TOTAL_AMOUNT) > 100; | HAVING SUM(TOTAL_AMOUNT) > 100; | ||
'''generate a list of each book category along with the average profit, as you did earlier. This query needs to include the following data filters:''' | |||
* Show only book categories with an average profit greater than $15.00. | |||
* Include only the categories Computer, Children, and Business. | |||
'''The first filtering task should be done with a HAVING clause because it places a condition on an aggregated value. The second filtering task should be handled with a WHERE clause at the row level to include only the book rows in the specified categories before the aggregation is performed.''' | |||
== GROUPING SETS == | == GROUPING SETS == |
Revision as of 17:17, 8 November 2017
Returns queries in groups
SELECT SALES_DATE, SUM(TOTAL_AMOUNT) FROM SALES GROUP BY SALES_DATE ORDER BY SALES_DATE;
This will take the sales made on the dates add them and return a column with the date -> total amount
Grouping Data using Multiple Columns
SELECT SALES_DATE, PRODUCT_ID, SUM(TOTAL_AMOUNT) FROM SALES WHERE SALES_DATE BETWEEN '01-JAN-15' AND '31-JAN-15' GROUP BY SALES_DATE, PRODUCT_ID;
Ex: total sales volume for January group by day and product
Group by And HAVING
TOTAL SALES VOLUME FOR JANUARY BY AND AND PRODUCT AND TOTAL VOLUME GREATER THAN 1000
SELECT SALES_DATE, PRODUCT_ID, SUM(TOTAL_AMOUNT) FROM SALES WHERE SALES_DATE BETWEEN '01-JAN-15' AND '31-JAN-15' GROUP BY SALES_DATE, PRODUCT_ID HAVING SUM(TOTAL_AMOUNT) > 100;
generate a list of each book category along with the average profit, as you did earlier. This query needs to include the following data filters:
- Show only book categories with an average profit greater than $15.00.
- Include only the categories Computer, Children, and Business.
The first filtering task should be done with a HAVING clause because it places a condition on an aggregated value. The second filtering task should be handled with a WHERE clause at the row level to include only the book rows in the specified categories before the aggregation is performed.
GROUPING SETS
Enables performing multiple GROUP BY clauses with a single query.
SELECT name, category, AVG(retail) FROM publisher JOIN books USING (pubid) GROUP BY GROUPING SETS (name, category, (name,category),());
CUBE
Performs aggregations for all possible combinations of columns included.
SELECT name, category, AVG(retail) FROM publisher JOIN books USING (pubid) GROUP BY CUBE(name, category) ORDER BY name, category;
ROLLUP
Performs increasing levels of cumulative subtotals, based on the provided column list.
SELECT name, category, AVG(retail) FROM publisher JOIN books USING (pubid) GROUP BY ROLLUP(name, category) ORDER BY name, category;