CASE (Transact-SQL) - SQL Server (2023)

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Applies to: CASE (Transact-SQL) - SQL Server (1) SQL Server (all supported versions) CASE (Transact-SQL) - SQL Server (2) Azure SQL Database CASE (Transact-SQL) - SQL Server (3) Azure SQL Managed Instance CASE (Transact-SQL) - SQL Server (4) Azure Synapse Analytics CASE (Transact-SQL) - SQL Server (5) Analytics Platform System (PDW)

Evaluates a list of conditions and returns one of multiple possible result expressions.

The CASE expression has two formats:

  • The simple CASE expression compares an expression to a set of simple expressions to determine the result.

  • The searched CASE expression evaluates a set of Boolean expressions to determine the result.

Both formats support an optional ELSE argument.

CASE can be used in any statement or clause that allows a valid expression. For example, you can use CASE in statements such as SELECT, UPDATE, DELETE and SET, and in clauses such as <select_list>, IN, WHERE, ORDER BY, and HAVING.

(Video) T-SQL: CASE Statement

CASE (Transact-SQL) - SQL Server (6) Transact-SQL syntax conventions

Syntax

Syntax for SQL Server, Azure SQL Database and Azure Synapse Analytics.

-- Simple CASE expression:CASE input_expression WHEN when_expression THEN result_expression [ ...n ] [ ELSE else_result_expression ]END-- Searched CASE expression:CASE WHEN Boolean_expression THEN result_expression [ ...n ] [ ELSE else_result_expression ]END

Syntax for Parallel Data Warehouse.

CASE WHEN when_expression THEN result_expression [ ...n ] [ ELSE else_result_expression ]END

Note

To view Transact-SQL syntax for SQL Server 2014 and earlier, see Previous versions documentation.

Arguments

input_expression

The expression evaluated when the simple CASE format is used. input_expression is any valid expression.

WHEN when_expression

A simple expression to which input_expression is compared when the simple CASE format is used. when_expression is any valid expression. The data types of input_expression and each when_expression must be the same or must be an implicit conversion.

THEN result_expression

The expression returned when input_expression equals when_expression evaluates to TRUE, or Boolean_expression evaluates to TRUE. result expression is any valid expression.

(Video) Intermediate SQL Tutorial | Case Statement | Use Cases

ELSE else_result_expression

The expression returned if no comparison operation evaluates to TRUE. If this argument is omitted and no comparison operation evaluates to TRUE, CASE returns NULL. else_result_expression is any valid expression. The data types of else_result_expression and any result_expression must be the same or must be an implicit conversion.

WHEN Boolean_expression

The Boolean expression evaluated when using the searched CASE format. Boolean_expression is any valid Boolean expression.

Note

To view Transact-SQL syntax for SQL Server 2014 and earlier, see Previous versions documentation.

Return types

Returns the highest precedence type from the set of types in result_expressions and the optional else_result_expression. For more information, see Data Type Precedence (Transact-SQL).

Return values

Simple CASE expression:

The simple CASE expression operates by comparing the first expression to the expression in each WHEN clause for equivalency. If these expressions are equivalent, the expression in the THEN clause will be returned.

  • Allows only an equality check.

    (Video) Case statement |SQL Server|SQL|SQL Tutorial #case #statement #sqlserver #sql

  • In the order specified, evaluates input_expression = when_expression for each WHEN clause.

  • Returns the result_expression of the first input_expression = when_expression that evaluates to TRUE.

  • If no input_expression = when_expression evaluates to TRUE, the SQL Server Database Engine returns the else_result_expression if an ELSE clause is specified, or a NULL value if no ELSE clause is specified.

Searched CASE expression:

  • Evaluates, in the order specified, Boolean_expression for each WHEN clause.

  • Returns result_expression of the first Boolean_expression that evaluates to TRUE.

  • If no Boolean_expression evaluates to TRUE, the Database Engine returns the else_result_expression if an ELSE clause is specified, or a NULL value if no ELSE clause is specified.

Remarks

SQL Server allows for only 10 levels of nesting in CASE expressions.

The CASE expression can't be used to control the flow of execution of Transact-SQL statements, statement blocks, user-defined functions, and stored procedures. For a list of control-of-flow methods, see Control-of-Flow Language (Transact-SQL).

(Video) TSQL: How To Use CASE WHEN Statements

The CASE expression evaluates its conditions sequentially and stops with the first condition whose condition is satisfied. In some situations, an expression is evaluated before a CASE expression receives the results of the expression as its input. Errors in evaluating these expressions are possible. Aggregate expressions that appear in WHEN arguments to a CASE expression are evaluated first, then provided to the CASE expression. For example, the following query produces a divide by zero error when producing the value of the MAX aggregate. This occurs prior to evaluating the CASE expression.

WITH Data (value)AS ( SELECT 0 UNION ALL SELECT 1 )SELECT CASE WHEN MIN(value) <= 0 THEN 0 WHEN MAX(1 / value) >= 100 THEN 1 ENDFROM Data;GO

You should only depend on order of evaluation of the WHEN conditions for scalar expressions (including non-correlated subqueries that return scalars), not for aggregate expressions.

You must also ensure that at least one of the expressions in the THEN or ELSE clauses isn't the NULL constant. While NULL can be returned from multiple result expressions, not all of these can explicitly be the NULL constant. If all result expressions use the NULL constant, error 8133 is returned.

Examples

A. Use a SELECT statement with a simple CASE expression

Within a SELECT statement, a simple CASE expression allows for only an equality check; no other comparisons are made. The following example uses the CASE expression to change the display of product line categories to make them more understandable.

USE AdventureWorks2019;GOSELECT ProductNumber, Category = CASE ProductLine WHEN 'R' THEN 'Road' WHEN 'M' THEN 'Mountain' WHEN 'T' THEN 'Touring' WHEN 'S' THEN 'Other sale items' ELSE 'Not for sale' END, NameFROM Production.ProductORDER BY ProductNumber;GO

B. Use a SELECT statement with a searched CASE expression

Within a SELECT statement, the searched CASE expression allows for values to be replaced in the result set based on comparison values. The following example displays the list price as a text comment based on the price range for a product.

USE AdventureWorks2019;GOSELECT ProductNumber, Name, "Price Range" = CASE WHEN ListPrice = 0 THEN 'Mfg item - not for resale' WHEN ListPrice < 50 THEN 'Under $50' WHEN ListPrice >= 50 AND ListPrice < 250 THEN 'Under $250' WHEN ListPrice >= 250 AND ListPrice < 1000 THEN 'Under $1000' ELSE 'Over $1000' ENDFROM Production.ProductORDER BY ProductNumber;GO

C. Use CASE in an ORDER BY clause

The following examples use the CASE expression in an ORDER BY clause to determine the sort order of the rows based on a given column value. In the first example, the value in the SalariedFlag column of the HumanResources.Employee table is evaluated. Employees that have the SalariedFlag set to 1 are returned in order by the BusinessEntityID in descending order. Employees that have the SalariedFlag set to 0 are returned in order by the BusinessEntityID in ascending order. In the second example, the result set is ordered by the column TerritoryName when the column CountryRegionName is equal to 'United States' and by CountryRegionName for all other rows.

SELECT BusinessEntityID, SalariedFlagFROM HumanResources.EmployeeORDER BY CASE SalariedFlag WHEN 1 THEN BusinessEntityID END DESC, CASE WHEN SalariedFlag = 0 THEN BusinessEntityID END;GO
SELECT BusinessEntityID, LastName, TerritoryName, CountryRegionNameFROM Sales.vSalesPersonWHERE TerritoryName IS NOT NULLORDER BY CASE CountryRegionName WHEN 'United States' THEN TerritoryName ELSE CountryRegionName END;GO

D. Use CASE in an UPDATE statement

The following example uses the CASE expression in an UPDATE statement to determine the value that is set for the column VacationHours for employees with SalariedFlag set to 0. When subtracting 10 hours from VacationHours results in a negative value, VacationHours is increased by 40 hours; otherwise, VacationHours is increased by 20 hours. The OUTPUT clause is used to display the before and after vacation values.

USE AdventureWorks2019;GOUPDATE HumanResources.EmployeeSET VacationHours = ( CASE WHEN ((VacationHours - 10.00) < 0) THEN VacationHours + 40 ELSE (VacationHours + 20.00) END )OUTPUT Deleted.BusinessEntityID, Deleted.VacationHours AS BeforeValue, Inserted.VacationHours AS AfterValueWHERE SalariedFlag = 0;GO

E. Use CASE in a SET statement

The following example uses the CASE expression in a SET statement in the table-valued function dbo.GetContactInfo. In the AdventureWorks2019 database, all data related to people is stored in the Person.Person table. For example, the person may be an employee, vendor representative, or a customer. The function returns the first and last name of a given BusinessEntityID and the contact type for that person. The CASE expression in the SET statement determines the value to display for the column ContactType based on the existence of the BusinessEntityID column in the Employee, Vendor, or Customer tables.

USE AdventureWorks2019;GOCREATE FUNCTION dbo.GetContactInformation (@BusinessEntityID INT)RETURNS @retContactInformation TABLE ( BusinessEntityID INT NOT NULL, FirstName NVARCHAR(50) NULL, LastName NVARCHAR(50) NULL, ContactType NVARCHAR(50) NULL, PRIMARY KEY CLUSTERED (BusinessEntityID ASC) )AS-- Returns the first name, last name and contact type for the specified contact.BEGIN DECLARE @FirstName NVARCHAR(50), @LastName NVARCHAR(50), @ContactType NVARCHAR(50); -- Get common contact information SELECT @BusinessEntityID = BusinessEntityID, @FirstName = FirstName, @LastName = LastName FROM Person.Person WHERE BusinessEntityID = @BusinessEntityID; SET @ContactType = CASE -- Check for employee WHEN EXISTS ( SELECT * FROM HumanResources.Employee AS e WHERE e.BusinessEntityID = @BusinessEntityID ) THEN 'Employee' -- Check for vendor WHEN EXISTS ( SELECT * FROM Person.BusinessEntityContact AS bec WHERE bec.BusinessEntityID = @BusinessEntityID ) THEN 'Vendor' -- Check for store WHEN EXISTS ( SELECT * FROM Purchasing.Vendor AS v WHERE v.BusinessEntityID = @BusinessEntityID ) THEN 'Store Contact' -- Check for individual consumer WHEN EXISTS ( SELECT * FROM Sales.Customer AS c WHERE c.PersonID = @BusinessEntityID ) THEN 'Consumer' END; -- Return the information to the caller IF @BusinessEntityID IS NOT NULL BEGIN INSERT @retContactInformation SELECT @BusinessEntityID, @FirstName, @LastName, @ContactType; END; RETURN;END;GOSELECT BusinessEntityID, FirstName, LastName, ContactTypeFROM dbo.GetContactInformation(2200);GOSELECT BusinessEntityID, FirstName, LastName, ContactTypeFROM dbo.GetContactInformation(5);GO

F. Use CASE in a HAVING clause

The following example uses the CASE expression in a HAVING clause to restrict the rows returned by the SELECT statement. The statement returns the hourly rate for each job title in the HumanResources.Employee table. The HAVING clause restricts the titles to those that are held by salaried employees with a maximum pay rate greater than 40 dollars, or non-salaried employees with a maximum pay rate greater than 15 dollars.

(Video) TSQL CASE Statement

USE AdventureWorks2019;GOSELECT JobTitle, MAX(ph1.Rate) AS MaximumRateFROM HumanResources.Employee AS eINNER JOIN HumanResources.EmployeePayHistory AS ph1 ON e.BusinessEntityID = ph1.BusinessEntityIDGROUP BY JobTitleHAVING ( MAX(CASE WHEN SalariedFlag = 1 THEN ph1.Rate ELSE NULL END) > 40.00 OR MAX(CASE WHEN SalariedFlag = 0 THEN ph1.Rate ELSE NULL END) > 15.00 )ORDER BY MaximumRate DESC;GO

Examples: Azure Synapse Analytics and Analytics Platform System (PDW)

G. Use a SELECT statement with a CASE expression

Within a SELECT statement, the CASE expression allows for values to be replaced in the result set based on comparison values. The following example uses the CASE expression to change the display of product line categories to make them more understandable. When a value doesn't exist, the text "Not for sale' is displayed.

-- Uses AdventureWorksSELECT ProductAlternateKey, Category = CASE ProductLine WHEN 'R' THEN 'Road' WHEN 'M' THEN 'Mountain' WHEN 'T' THEN 'Touring' WHEN 'S' THEN 'Other sale items' ELSE 'Not for sale' END, EnglishProductNameFROM dbo.DimProductORDER BY ProductKey;GO

H. Use CASE in an UPDATE statement

The following example uses the CASE expression in an UPDATE statement to determine the value that is set for the column VacationHours for employees with SalariedFlag set to 0. When subtracting 10 hours from VacationHours results in a negative value, VacationHours is increased by 40 hours; otherwise, VacationHours is increased by 20 hours.

-- Uses AdventureWorksUPDATE dbo.DimEmployeeSET VacationHours = ( CASE WHEN ((VacationHours - 10.00) < 0) THEN VacationHours + 40 ELSE (VacationHours + 20.00) END )WHERE SalariedFlag = 0;GO

See also

  • Expressions (Transact-SQL)
  • SELECT (Transact-SQL)
  • COALESCE (Transact-SQL)
  • IIF (Transact-SQL)
  • CHOOSE (Transact-SQL)

FAQs

How to use case statement in SQL Server? ›

The CASE statement can be used in SQL Server (Transact-SQL). SELECT contact_id, CASE WHEN website_id = 1 THEN 'TechOnTheNet.com' WHEN website_id = 2 THEN 'CheckYourMath.com' ELSE 'BigActivities.com' END FROM contacts; One thing to note is that the ELSE condition within the CASE statement is optional.

Does SQL Server use SQL or T-SQL? ›

T-SQL, which stands for Transact-SQL and is sometimes referred to as TSQL, is an extension of the SQL language used primarily within Microsoft SQL Server. This means that it provides all the functionality of SQL but with some added extras.

What is Transact SQL in SQL Server? ›

T-SQL (Transact-SQL) is a set of programming extensions from Sybase and Microsoft that add several features to the Structured Query Language (SQL), including transaction control, exception and error handling, row processing and declared variables.

How to write multiple conditions in CASE statement in SQL Server? ›

Here are 3 different ways to apply a case statement using SQL:
  1. (1) For a single condition: CASE WHEN condition_1 THEN result_1 ELSE result_2 END AS new_field_name.
  2. (2) For multiple conditions using AND: CASE WHEN condition_1 AND condition_2 THEN result_1 ELSE result_2 END AS new_field_name.
Aug 6, 2021

What are the two types of CASE statement in SQL? ›

There are two types of SQL CASE statements: a simple CASE statement and a searched CASE statement. Simple CASE statements determine the result value evaluating an expression against multiple values. Searched CASE statements determine the result value evaluating a set of Boolean expressions.

What are CASE statements in SQL give examples? ›

A SQL CASE statement evaluates and returns results based on particular values, predicates and conditions as per defined logic. For example, suppose you have a voters table with the following details: Voter ID. Name.

What are the advantages of T-SQL? ›

Advantages of T-SQL
  • Processing of Query is Fast: T-SQL allows the data administrator to quickly retrieve data from the database and process large amounts of data. ...
  • Interactive in Nature: The T-SQL programming language can be used to write intricate business rules, which can then be used to retrieve data from a database.

Is T-SQL worth learning? ›

Being an expert in T-SQL and MS SQL Server gives you a great chance for employment with good earnings. Learn about the positions you could get with MS SQL by reading Types of Database Jobs: Choose One of Them and Start Being Awesome. From the entrepreneur's point of view, it is worth choosing Microsoft software.

Should I learn SQL or T-SQL? ›

Whether you're a database admin, a developer, or an engineer, T-SQL's complex syntax gives you the ability to do more. To enhance your SQL knowledge, you should immerse yourself in T-SQL first, not SQL.

What are the types of transactions in SQL Server? ›

SQL Server provides the following transaction statements:
  • BEGIN DISTRIBUTED TRANSACTION. ROLLBACK TRANSACTION.
  • BEGIN TRANSACTION. ROLLBACK WORK.
  • COMMIT TRANSACTION. SAVE TRANSACTION.
  • COMMIT WORK.
Nov 18, 2022

What are the different types of statements available to you in T-SQL? ›

Types of SQL Statements
  • Data Definition Language (DDL) Statements.
  • Data Manipulation Language (DML) Statements.
  • Transaction Control Statements.
  • Session Control Statements.
  • System Control Statement.
  • Embedded SQL Statements.

What is T-SQL in stored procedure? ›

Stored procedures are a collection of Transact-SQL statements stored within the database. They are used to encapsulate oft-used queries, such as conditional statements, loops, and other powerful programming features.

Can I write 2 conditions in if statement? ›

Here we'll study how can we check multiple conditions in a single if statement. This can be done by using 'and' or 'or' or BOTH in a single statement. and comparison = for this to work normally both conditions provided with should be true. If the first condition falls false, the compiler doesn't check the second one.

Can I put condition in CASE statement? ›

The CASE expression goes through conditions and returns a value when the first condition is met (like an if-then-else statement). So, once a condition is true, it will stop reading and return the result. If no conditions are true, it returns the value in the ELSE clause.

How do you write a nested CASE statement in SQL? ›

Try some sort of COALESCE trick: SELECT COALESCE( CASE WHEN condition1 THEN calculation1 ELSE NULL END, CASE WHEN condition2 THEN calculation2 ELSE NULL END, etc... )

Which are 3 different types of SQL statements that you can execute? ›

DDL DML DCL SQL sentences

There are 3 main types of commands. DDL (Data Definition Language) commands, DML (Data Manipulation Language) commands, and DCL (Data Control Language) commands. Let's talk about them.

What is the syntax for CASE statement in SQL? ›

SQL Server CASE statement syntax

It starts with the CASE keyword followed by the WHEN keyword and then the CONDITION. The condition can be any valid SQL Server expression which returns a boolean value. For instance, the condition can be model > 2000, the THEN clause is used after the CONDITION.

How do you write a case statement? ›

The case statement should include your mission, vision and values statements, and should set out to clearly answer the who, what, and why of your fundraising efforts. The Alaska Food Coalition offers some questions that an effective case statement might seek to answer: - How does this organization help people?

Where do I put the case statement in SQL query? ›

The CASE statement always goes in the SELECT clause. CASE must include the following components: WHEN , THEN , and END . ELSE is an optional component. You can make any conditional statement using any conditional operator (like WHERE ) between WHEN and THEN .

What are the two formats of the CASE expressions? ›

The CASE expression has two formats:
  • The simple CASE expression compares an expression to a set of simple expressions to determine the result.
  • The searched CASE expression evaluates a set of Boolean expressions to determine the result.
Nov 18, 2022

How long does it take to learn T-SQL? ›

Because SQL is a relatively simple language, learners can expect to become familiar with the basics within two to three weeks. That said, if you're planning on using SQL skills at work, you'll probably need a higher level of fluency. How quickly you achieve mastery will depend on your method of learning.

Is T-SQL the same as MySQL? ›

T-SQL means only SQL server? T-SQL works, as Gordon said, in Microsoft SQL Server and Sybase. It does not work in MySQL; that rdbms uses a different SQL dialect. If your instruction says "create a database using T-SQL", that means you must use Microsoft SQL Server or maybe Sybase.

Is T-SQL the same as PL SQL? ›

T-SQL was originally developed by Sybase and now owned by Microsoft. Hence, it works with Microsoft SQL Server only. P/L SQL was developed by Oracle and works with Oracle only. All database objects like Tables/Views/Procedures are internally organized by database names.

Will SQL become obsolete? ›

With so many companies relying on relational databases and so many data professionals trained to work with SQL, these tools are not going away in the near future.

Can I learn SQL in 2 days? ›

It should take an average learner about two to three weeks to master the basic concepts of SQL and start working with SQL databases. But in order to start using them effectively in real-world scenarios, you'll need to become quite fluent; and that takes time.

Which SQL is most in demand? ›

As of August 2022, the most popular database management system (DBMS) in the world was Oracle, with a ranking score of 1260.8; MySQL and Microsoft SQL server rounded out the top three.

Which is harder to learn SQL or Python? ›

If we look at it as a language, then SQL is much easier as compared to Python because the syntax is smaller, and there are pretty few concepts in SQL. On the other hand, if you look at it as a tool, then SQL is tougher than coding in Python.

Is Python and SQL enough to get a job? ›

Yes, knowing the fundamentals of more general languages like Python or R is critical. However, ignoring SQL will make it much harder to get a job in data. Here are three key reasons why you absolutely need to learn SQL in 2023.

What is the best tool to learn SQL? ›

6 Best Free Resources for Learning SQL
  • SQLZoo. SQLZoo is an interactive, Wiki-based tutorial that offers lessons and projects for beginners in SQL. ...
  • Codecademy. Codecademy, a leading educational coding platform, offers a free course on SQL. ...
  • SQLBolt.

What are the 4 transactions? ›

The four types of financial transactions are purchases, sales, payments, and receipts. Businesses use the accrual or cash method of accounting to record such transactions.

What are the 3 transactions? ›

Based on the exchange of cash, there are three types of accounting transactions, namely cash transactions, non-cash transactions, and credit transactions.

What are the 3 stages of transaction? ›

It should be customized for each and every user in the ecosystem. According to Garg, transactions happen in three stages in a bank or any other financial services industry that has adopted digitization. The three stages include information, communication and transaction.

What are the 5 types of SQL commands? ›

These SQL commands are mainly categorized into five categories as:
  • DDL – Data Definition Language.
  • DQL – Data Query Language.
  • DML – Data Manipulation Language.
  • DCL – Data Control Language.
  • TCL – Transaction Control Language.
Nov 30, 2022

What are the 5 basic SQL queries? ›

Some of The Most Important SQL Commands
  • SELECT - extracts data from a database.
  • UPDATE - updates data in a database.
  • DELETE - deletes data from a database.
  • INSERT INTO - inserts new data into a database.
  • CREATE DATABASE - creates a new database.
  • ALTER DATABASE - modifies a database.
  • CREATE TABLE - creates a new table.

What are the 4 major types of command types in SQL? ›

SQL Commands can be grouped into following depending on their functionality:
  • DDL (Data Definition Language)
  • DML (Data Manipulation Language)
  • TCL (Transaction Control Language)
  • DCL (Data Control Language)
Jan 23, 2020

How do I run T-SQL? ›

Run the script file
  1. Open a command prompt window.
  2. In the Command Prompt window, type: sqlcmd -S myServer\instanceName -i C:\myScript.sql.
  3. Press ENTER.
Nov 18, 2022

How to create a stored procedure in T-SQL? ›

Using SQL Server Management Studio

Right-click Stored Procedures, and then click New Stored Procedure. On the Query menu, click Specify Values for Template Parameters. In the Specify Values for Template Parameters dialog box, enter the following values for the parameters shown. Returns employee data.

What is the difference between SQL function and stored procedure? ›

In a function, it is mandatory to use the RETURNS and RETURN arguments, whereas in a stored procedure is not necessary. In few words, a stored procedure is more flexible to write any code that you want, while functions have a rigid structure and functionality.

How do you use the IF formula for multiple conditions? ›

How to use IF function with multiple conditions. In essence, there are two types of the IF formula with multiple criteria based on the AND / OR logic. Consequently, in the logical test of your IF formula, you should use one of these functions: AND function - returns TRUE if all the conditions are met; FALSE otherwise.

Can IF statement have 3 conditions? ›

You can use the following formulas to create an IF function with 3 conditions in Excel:
  • Method 1: Nested IF Function =IF(C2<15, "Bad", IF(C2<20, "OK", IF(C2<25, "Good", "Great")))
  • Method 2: IF Function with AND Logic =IF(AND(A2="Mavs", B2="Guard", C2>25), "Yes", "No")
Jul 24, 2022

How do I use multiple conditions? ›

You can use the OR condition in the WHERE clause to test multiple conditions where the record is returned if any one of the conditions are met. This example uses the WHERE clause to define multiple conditions, but instead of using the AND condition, it uses the OR condition.

Can we use subquery in CASE? ›

To answer your question, Yes, you can have a subquery inside a Case statement.

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.

How to use inner CASE in SQL? ›

In the Nested CASE expression, the outer statement executes until satisfying a condition. Once the condition is met, the inner CASE expression executes and returns a single result. If no condition is met in the outer statement, CASE expression returns the value in the ELSE statement.

Where do I put the CASE statement in SQL query? ›

The CASE statement always goes in the SELECT clause. CASE must include the following components: WHEN , THEN , and END . ELSE is an optional component. You can make any conditional statement using any conditional operator (like WHERE ) between WHEN and THEN .

How do you create a case in SQL Server? ›

Convert UPPER Case and LOWER Case to Proper Case/Title Case in SQL Server
  1. CREATE FUNCTION [dbo].[ProperCase]
  2. (
  3. @Input as varchar(8000)
  4. )
  5. RETURNS varchar(8000)
  6. AS.
  7. BEGIN.
  8. DECLARE @Reset bit,
Jun 25, 2016

How to use case in SQL Server stored procedure? ›

CASE statements can be used to conditionally enter into some logic based on the status of a condition being satisfied. There are two types of CASE statements: Simple case statement: used to enter into some logic based on a literal value.

How do you write a CASE statement? ›

The case statement should include your mission, vision and values statements, and should set out to clearly answer the who, what, and why of your fundraising efforts. The Alaska Food Coalition offers some questions that an effective case statement might seek to answer: - How does this organization help people?

How is CASE statement executed? ›

The CASE statement selects a sequence of statements to execute. To select the sequence, the CASE statement uses a selector (an expression whose value is used to select one of several alternatives) or, in the searched CASE statement, multiple search conditions.

Can we write subquery in CASE statement? ›

To answer your question, Yes, you can have a subquery inside a Case statement.

Is case important in SQL? ›

Keywords in SQL are case-insensitive for the most popular DBMSs. The computer doesn't care whether you write SELECT , select, or sELeCt ; so, in theory, you can write however you like.

How to convert string into title case in SQL Server? ›

Run Following T-SQL statement in query analyzer: SELECT dbo. udf_TitleCase('This function will convert this string to title case!'

How do I change the case in SQL? ›

If you want to display a string in uppercase, use the SQL UPPER() function. This function takes only one argument: the string column that you want to convert to uppercase.

How do you use a CASE in WHERE clause? ›

CASE STATEMENT IN WHERE CLAUSE:

We can use a case statement in Where, Order by and Group by clause. In the Customer table, I have displayed the First Name is Ram or the Last Name is Sharma's salary. So, by using a CASE statement with the where condition displays the result.

Can we use CASE statement in update query? ›

You can also use CASE in an UPDATE statement. The SQL UPDATE statement is used to change values in an existing table.

Can I use CASE in FROM clause SQL? ›

No, you can't pick a table to query using a CASE statement. CASE statements only go within expressions, such as for a column's value or as part of your WHERE expression.

How do you test a CASE in SQL? ›

A typical SQL unit testing scenario is as follows:
  1. Create a database object to meet some business requirement.
  2. Create a SQL unit test to check the database object.
  3. Run SQL unit test to check the database object does the job or not.
  4. If the test is passed then move on to the next SQL unit test.
Jun 14, 2019

Why do we use case statements? ›

The CASE statement in SQL returns a value for the condition specified. It tests a list of conditions and returns one of the multiple possible results. We mostly use a case expression in SQL stored procedures or as a formula for a particular column which optimizes the SQL statements.

What are the four basic SQL syntax or queries? ›

In Data Manipulation Language(DML), we have four different SQL statements, Select, Insert, Update, and Delete.

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