What Are Group Functions in Oracle

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What Are Group Functions in Oracle?

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A

Group functions are functions applied to a group of rows. Examples of group functions are:

COUNT(*) - Returns the number of rows in the group.
MIN(exp) - Returns the minimum value of the expression evaluated on each row of the group.
MAX(exp) - Returns the maximum value of the expression evaluated on each row of the group.
AVG(exp) - Returns the average value of the expression evaluated on each row of the group.

⇒ Use Group Functions in the SELECT Clause in Oracle

⇐ Filter Out Duplications in Returning Rows in Oracle

⇑ Understanding SQL SELECT Query Statements in Oracle

⇑⇑ Oracle Database Tutorials

2019-12-19, 1946🔥, 0💬

Group Functions Used with Non-group Selection Fields in Oracle
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Count the Number of Rows with SELECT Statements in Oracle
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Sort Query Output in Descending Order in Oracle
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Use Group Functions in the SELECT Clause in Oracle
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What Are Group Functions in Oracle
What Are Group Functions in Oracle? Group functions are functions applied to a group of rows. Examples of group functions are: COUNT(*) - Returns the number of rows in the group. MIN(exp) - Returns the minimum value of the expression evaluated on each row of the group. MAX(exp) - Returns the maximum... 2019-12-19, 1947🔥, 0💬

Use of SELECT Statements in Views in Oracle
Can SELECT Statements Be Used on Views in Oracle? Select (query) statements can used on views in the same way as tables. The following tutorial exercise helps you creating a view and running a query statement on the view: SQL> CREATE VIEW managed_dept AS SELECT * FROM departments WHERE manage... 2019-12-19, 1936🔥, 0💬

Count Duplicated Values in a Column in Oracle
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Filter Out Duplications in Returning Rows in Oracle
How To Filter Out Duplications in Returning Rows in Oracle? If there are duplications in the returning rows, and you want to remove the duplications, you can use the keyword DISTINCT or UNIQUE in the SELECT clause. The tutorial exercise below shows you that DISTINCT works on selected columns only: S... 2019-12-19, 1897🔥, 0💬

Apply Filtering Criteria at Group Level in Oracle
How To Apply Filtering Criteria at Group Level in Oracle? If you want to return only specific groups from the query, you can apply filtering criteria at the group level by using the HAVING clause inside the GROUP BY clause. The following script gives you a good HAVING example: SQL> SELECT dep... 2019-11-21, 1880🔥, 0💬

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