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Group By and Having clause

 Group By and Having The GROUP BY statement groups rows that have the same values into summary rows, like "find the number of customers in each dept". The GROUP BY statement is must be used with aggregate functions (COUNT, MAX, MIN, SUM, AVG) to group the result-set by one or more columns. GROUP BY Syntax
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Sql-Keywords (distinct , order by) and where clause

 Sql-Keywords (distinct , order by) and where clause

Distinct Keyword


The DISTINCT keyword is used to return only distinct (unique) column values.
Sql tables often contains many duplicate values in columns and sometimes you only want to list the unique(distinct) values.

sample table :


In table we can multiple name with same values.

to view on distinct column value following distinct command to execute

Select distinct empname from k4coding_emp




Distinct Keyword:

The ORDER BY keyword is used to sort the  output  in ascending or descending order.

ORDER BY Syntax
SELECT col1, col2,col3, ...
FROM tablename
ORDER BY col1, col2, ... ASC|DESC;

The ORDER BY keyword sorts the records in ascending order by default. 
Select * from k4coding_emp order by empname




To sort the records in descending order, use the DESC keyword.

Select * from k4coding_emp order by empname desc



Where Clause:

The SQL WHERE clause is used to filter the records, it contains logical conditions .
The WHERE clause is used to extract only those records that fulfill a specified condition.

WHERE clause  Syntax
SELECT col1, col2, ...
FROM table_name
WHERE condition;

Select * from k4coding_emp
where dept ='HR'




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