How to use orderby in sql

The OrderBy clause is used to sort SQL query results by the specified column. Syntax: SELECT ... ORDER BY column1 [ASC|DESC], column2 [ASC|DESC], ... Parameters: 1. Column to be sorted 2. Optional sort order: [ASC (ascending) | DESC (descending) )]

Usage of OrderBy in SQL

The OrderBy clause is used to match the SQL query results according to the specified column to sort.

Syntax:

##SELECT ... ORDER BY column1 [ASC|DESC], column2 [ASC|DESC], ...

Parameters:

• column1, column2, ...: the column to be sorted
• ASC: Sort in ascending order (from small to large)
• DESC: Sort in descending order (from large to small)

Usage:

1. Single column sort:

<code class="sql">SELECT name, age FROM customers ORDER BY name ASC;</code>

This will sort the results by customer name in ascending order.

2. Multiple column sorting:

<code class="sql">SELECT name, age, city FROM customers ORDER BY name ASC, age DESC;</code>

This will sort first by name in ascending order, then by age in descending order.

3. Sort Descending:

<code class="sql">SELECT name, age FROM customers ORDER BY age DESC;</code>

This will sort the results in descending order by age.

4. NULL value handling:

By default, NULL values ​​are treated as smaller than non-NULL values. NULL values ​​can be handled using the

COALESCE() function, for example:

<code class="sql">SELECT name, age FROM customers ORDER BY COALESCE(age, 0) ASC;</code>

This will sort by age in ascending order, treating NULL values ​​as 0.

5. Composite sorting:

You can sort using composite columns, for example:

<code class="sql">SELECT name, city, state FROM customers ORDER BY name ASC, city DESC;</code>

This will sort each state first Sort by name in ascending order and then by city in descending order.

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