Can case when be used after where in sql?

In SQL, CASE WHEN can be used in the WHERE clause. Used to specify different results when a condition is true or not true, thereby filtering data and selecting only rows that meet specific conditions. The syntax is: WHERE CASE WHEN THEN WHEN THEN ... ELSE END.

Can CASE WHEN

in the WHERE clause of SQL be used in the WHERE clause? CASE WHEN?

Yes, you can use the CASE WHEN statement in the WHERE clause.

how to use?

The CASE WHEN statement is used to specify different results when a condition is true or not. In the WHERE clause, it can be used to filter data and select only rows that meet certain criteria.

Syntax:

<code>WHERE CASE
    WHEN <condition1> THEN <result1>
    WHEN <condition2> THEN <result2>
    ...
    ELSE <default_result>
END</code>

Example:

<code>SELECT * FROM table_name
WHERE CASE
    WHEN age > 18 THEN 'Adult'
    WHEN age BETWEEN 13 AND 18 THEN 'Teen'
    ELSE 'Child'
END;</code>

This query will select all from the table named "table_name" rows and classify them as "Adult", "Teen" or "Child" based on their "age" column.

Note:

• CASE WHEN can be used as an expression in the WHERE clause.
• Make sure to specify a default result to handle all cases where none of the conditions are met.
• CASE WHEN can be nested, allowing complex conditions.

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