Can you do nested case statements in SQL?

Can you do nested case statements in SQL?

CASE can be nested in another CASE as well as in another IF…ELSE statement. In addition to SELECT, CASE can be used with another SQL clause like UPDATE, ORDER BY.

How do you write a case statement in a SQL case?

SQL CASE Statement

1. CASE. WHEN condition1 THEN result1. WHEN condition2 THEN result2. WHEN conditionN THEN resultN. ELSE result.
2. Example. SELECT OrderID, Quantity, CASE. WHEN Quantity > 30 THEN ‘The quantity is greater than 30’
3. Example. SELECT CustomerName, City, Country. FROM Customers. (CASE.

How do nested queries work?

A subquery, also known as a nested query or subselect, is a SELECT query embedded within the WHERE or HAVING clause of another SQL query. The data returned by the subquery is used by the outer statement in the same way a literal value would be used.

What is difference between subquery and nested query?

When a query is included inside another query, the Outer query is known as Main Query, and Inner query is known as Subquery. In Nested Query, Inner query runs first, and only once. Outer query is executed with result from Inner query. Hence, Inner query is used in execution of Outer query.

What is a case when statement in SQL?

CASE is the special scalar expression or conditional statement in the SQL language which returns a single value based on the evaluation of a statement. It can be used in Select, Where and Order By clause. A Case expression is mostly used in SQL stored procedures or as a formula for a particular column, which optimizes the SQL statements.

What is Case Logic in SQL?

SQL CASE is a very unique conditional statement providing if/then/else logic for any ordinary SQL command, such as SELECT or UPDATE. It then provides when-then-else functionality (WHEN this condition is met THEN do_this).

What is a SELECT CASE statement?

A Select Case statement allows a variable to be tested for equality against a list of values. Each value is called a case, and the variable being switched on is checked for each select case.

What is a SELECT query in SQL?

A select query is a data retrieval query, while an action query asks for additional operations on the data, such as insertion, updating or deletion. Query languages are used to make queries in a database, and Microsoft Structured Query Language (SQL) is the standard.